Pasture renewal required after grass grub/porina damage
Region: Hawke’s Bay, Manawatu-Wanganui, Marlborough, Nelson/Tasman, Otago, Southland, Taranaki, Wellington,West Coast, Canterbury, Gisborne
For pastures badly affected by either grass grub or porina over winter and needing renewal consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Direct drilling new pasture?
Region: All of NZ
If pasture establishment by direct drilling is going to be used check those pastures for pests, especially slugs and feeding grass grub as even low numbers can devastate young seedlings of pasture or crop plants.
In yellow bristle grass infested pastures consider….
Region: Northland, Auckland, BOP, Waikato, Taranaki, Marlborough, Canterbury
If pasture is near the end of its life was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
If your pasture is still strong but was infested with YBG consider locking it up for silage to reduce germination of YBG in the early summer. However, do not make it into hay as that will only spread the YBG.
Ordering grass seed?
Region: All of NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector at www.dairynzfvi.co.nz
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Clover root weevils in pasture may reduce amount of N fixed by clover.
Region: All of NZ
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Northern North Island watch for clover flea damage to clover
Region: Auckland, Waikato, Northland, BOP
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Clover flea > Direct Drilling > Grass > Grass grub > Porina > Yellow bristle grass
Pest damage showing in pastures.
Region: All of NZ
Damage to pastures often becomes very obvious in winter. Generally it is too late to prevent production losses which have already occurred but pastures may be saved and long term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Porina and Grass grub damage is showing in lower North Island.
Region: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Porina and grass grub damage is showing in lower North Island. The only option available to protect pasture now is insecticide
Social tagging: AgPest > Grass grub > PorinaGrass grub (yellow patches) and porina (bare ground) damage showing.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. At this time of year conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Porina damage in southern North Island from late moth flights may be apparent.
Region: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Porina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching control may only be warranted if it is required to preserve pasture plants.
Apply broadleaved weed herbicide to established pastures if needed once clover growth has slowed.
Region: All of NZ
Check established pastures for seedling broadleaved weeds such as nodding or winged thistle, ragwort or other troublesome weed and apply herbicide as necessary to the young weeds once clover growth has slowed.
Social tagging: AgPest > Grass grub > Porina > Tasmanian grass grub beetleGrass grub (yellow patches) and porina (bare ground) damage showing.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures. Porina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay, Otago
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. This pest is now established in Central Otago.
Make preparations for winter spraying of weeds if required.
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Make preparations for winter spraying of weeds if required. Scout paddocks and map infestations of weeds such as ragwort, thistles. Develop strategies for ongoing management of weedy areas, e.g. grazing, set-aside, spraying, nutrient or lime applications etc.
Social tagging: Grass grub > Porina > Tasmanian grass grub beetleGrass grub damage will be showing up by now.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub damage is indicated by patches of pasture turning yellow and later becoming soft under foot. Pasture can be easily pulled back which is likely to reveal larvae feeding near the surface. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of Porina using diflubenzuron, except for caterpillars from late February/March flights in the North Island and the South Island West Coast which are still susceptible. In most cases Porina control now needs to be by conventional insecticide.
After dry periods or hard grazing over summer, some pastures are open to infestations of winter weeds.
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Check new pastures for autumn germinating weeds such as thistles, ragwort, hedge mustard, annual buttercup, storksbill, chickweed etc. and apply herbicide as necessary to control broadleaved weeds (6-8 weeks after establishment).
Black beetle are now in the adult stage.
Region: Northland, Auckland, BoP, Waikato
Black beetle now infest large parts of the North Island with damaging populations occurring as far south as coastal parts of Manawatu and Hawkes Bay. Endophytes such as AR37, and NEA2 deter the adult beetle from laying eggs in spring and thereby reduce larval numbers. To maximise the effects of endophyte, it is important that infection levels are high in ryegrass or tall fescue and that the pastures are not infested by other host grasses such as kikuyu or paspalum. See DairyNZ Pasture Renewal Guide
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay, Waikato, Manawatu, Canterbury, Otago
Unlike the NZ native grass grub, Tasmanian grass grub live underground and feed on herbage. Damage appears areas of poor pasture growth. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. This pest is now occurs throughout much of New Zealand.
Social tagging: Black beetle > Grass grub > Porina > Tasmanian grass grub beetleInspect young pastures for grass grub and porina.
Regions: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
In grass grub or porina prone areas check pastures for damage. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft under foot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control, conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island are still susceptible. In most cases porina control now needs to be by conventional insecticide.
Direct drilling new pasture? Look for slugs and grass grub.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
If pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Small weeds can be effectively controlled with herbicides which are soft on clovers but if the weeds get too large they can only be controlled with herbicides which also damage clovers.
Damage from black beetle larvae showing.
Regions: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Northern North Island watch for clover flea damage.
Regions: Northland, Auckland, Bay of Plenty
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness. See New Zealand Novachem Agrichemical Manual.
Tasmanian grass grub damage may be seen.
Regions: Gisborne, Hawkes Bay, Canterbury, Central Otago
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Velvetleaf and other weeds will be well into flowering now.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Velvetleaf and other weeds will be well into flowering now. If you notice a new weed get it identified. Any new plants that are appearing on your property or in your crops should be identified to a) assist you in managing it in the future, and b) to check that it is not a new incursion that should be dealt with on a wider scale. Send a clear photo(s) to AgPest to have it identified.
Social tagging: Black beetle > black beetle larvae > Clover flea > Grass grub > Porina > Slugs > Tasmanian grass grub beetle > Velvetleaf > WeedDirect drilling new pasture? Look for slugs and grass grub.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
If pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Small weeds can be effectively controlled with herbicides which are soft on clovers but if the weeds get too large they can only be controlled with herbicides which also damage clovers.
Wanting to control Californian thistle?
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Ordering grass seed? Select endophyte.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1,AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector on Dairy NZ’s Forage Value Index.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Late flights of porina occurring in lower North Island.
Regions: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Late flights of porina may occur in the North Island, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
Inspect 2 & 3 year old pastures for damaging levels of grubs.
Regions: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
In grass grub prone areas 2 and 3 year old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Northern North Island watch for clover flea damage.
Regions: Northland, Auckland, Bay of Plenty
Northern North Island watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Tasmanian grass grub damage may be showing.
Regions: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Due to dry weather the pastures are very open.
Regions: Northland, Auckland, Bay of Plenty, Waikato
There may be a flush of weeds after the first rain- treat if severe.
Pennyroyal can also become dominant after a drought and would need to be treated with 2,4-D early in spring if a problem.
Plantain moth numbers are building.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Plantain moth numbers are building up and may increase dramatically after rain if warm conditions continue. Check with agchem reps for insecticide options.
Velvetleaf in fodder beet crops.
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
In 2016 velvetleaf seed was introduced to New Zealand as a contaminant of fodder beet seed and planted in many properties throughout New Zealand. To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Last year was a cool year and no velvetleaf was found in the South Island but it was found at some North Island sites. This year is much warmer and more velvetleaf is expected to germinate. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, visit MPI or AgPest online or contact your regional council.
Weeds can be spread via imported hay.
Regions: Northland, Auckland, Bay of Plenty, Waikato
If importing hay from other farms / regions be aware of unwanted weeds- many weed seeds can survive in and be spread via hay. Record the areas where hay has been fed out and regularly check these areas for new weeds after autumn and late spring rains- get rid of unwanted weeds before they become established! If you don’t recognise a weed get it identified.
Social tagging: Argentine stem weevil > Black beetle > Californian thistle > Clover flea > Endophyte > Grass grub > grass seed > Pennyroyal > plantain moth > Porina > Slugs > Tasmanian grass grub beetle > Velvetleaf > WeedArgentine stem weevil a threat to seedling grasses
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection.
Damage from black beetle larvae may be showing
Regions: Northland, Auckland, BoP, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Second porina flight due
Regions: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
The early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight mid January to mid February is the optimal time to be applying diflubenzuron.
Ordering grass seed? Select endophyte
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Controlling Californian thistle
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Tasmanian grass grub beetle flights
Regions: Gisborne, Hawkes Bay, Canterbury, Central Otago
Watch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Clover root weevil damage
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent.
Clover root weevil pasture renewal
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Clover root weevil. Pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover free break crop provides a temporary weevil free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Grass grub prone areas
Regions: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
In grass grub prone areas 2 and 3 year old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Watch for clover flea damage
Regions: Northland, Auckland, BoP, Waikato
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Remain vigilant for velvetleaf
Regions: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Argentine stem weevil > Black beetle > Californian thistle > Clover > Clover flea > Clover root weevil > Endophyte > Grass grub > grass seed > Porina > Tasmanian grass grub beetle > VelvetleafAphids, diamondback moth and white butterfly caterpillars in brassica crops
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Watch for plantain caterpillars and moths
Regions: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Wanganui
Plantain moths and caterpillars populations maybe high or building up. Apply insecticide early to prevent damage occurring.
Damage from black beetle larvae may be showing
Regions: Northland, Auckland, BoP, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Tasmanian grass grub beetle flights
Regions: Gisborne, Hawkes Bay, Canterbury, Central Otago
Watch for Tasmanian grass grub beetle flights, large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Second significant flight of porina moths
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
The early flight of porina moths has passed but the second significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Argentine stem weevils will increase in significance over summer
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Argentine stem weevils increase in significance over summer. Be aware that seedling grasses, even those infected with endophyte, are very susceptible to damage from this pest if numbers are high. This also applies to cereal and maize crops. Coated seed or pre-emergence insecticide application can prevent damage.
Clover root weevil adults are abundant
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
Remain vigilant for velvetleaf
Regions: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Aphids > Argentine stem weevil > Black beetle > Caterpillar > Clover root weevil > Diamondback moth > plantain moth > Porina > Tasmanian grass grub beetle > Velvetleaf > White butterflyTasmanian grass grub beetle flights occurring
Region: All NZ
Tasmanian grass grub beetle flights occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Aphids, diamondback moth & white butterfly caterpillars in brassica crops
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Check sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Clover root weevil present in most areas
Regions: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Clover root weevil will be very obvious in most areas. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over grazed.
Apply herbicides to yellow bristle grass before seed heads ripen
Regions: Northland, Auckland, Waikato, BOP, Taranaki
Apply herbicides to yellow bristle grass before seed heads ripen. Avoid moving stock from infested to clean paddocks – seeds can survive in dung.
Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds can survive in hay. In contrast, yellow bristle grass seeds are highly unlikely to survive in well made silage and wrapped baleage.
Note porina flights from now on
Regions: Waikato, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Remain vigilant for velvetleaf in fodder beet
Region: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Aphids > Chilean needle grass > Clover root weevil > Diamondback moth > Grass grub > Porina > Tasmanian grass grub beetle > Velvetleaf > White butterfly > Yellow bristle grassClover root weevil present in most areas.
Region: All of NZ
Clover root weevil will be very obvious in most areas –U shaped notches at the edge of clover leaves show adults are present. The presence of larvae may be indicated by the pasture appearing nitrogen deficient. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over grazed.
Consider Argentine stem weevil in pasture/crop establishment.
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Argentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment. Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Check sunny slopes for Chilean needle grass with its reddish purple seed heads.
Region: All of NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Region: Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Check your sunny slopes for Chilean needle grass in November and December.
Region: All except West Coast of South Island
Chilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found here on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Tasmanian grass grub beetle flights occurring.
Region: All of NZ
Tasmanian grass grub beetle flights occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Be vigilant for new weeds which you have not seen before.
Region: All of NZ
In newly planted crops, scout for new weeds and weeds that have survived spraying with herbicides. Get these identified by sending photos to AgPest as they may be either a serious new incursion or have become resistant to herbicides. In either case it is important to get this sorted before they become established over large areas. Report weeds at www.agpest.co.nz/report
Watch out for Yellow Bristle Grass on the roadside, it is rapidly moving south.
Region: Canterbury, Marlborough, Nelson, Manawatu
Yellow bristle grass (YBG) is continuing to expand its range and is rapidly moving south into Manawatu and Canterbury. Watch for an upright grass with many compact, yellow-tinged seed heads appearing on the roadside. Take measures to stop it moving onto your farm. For more details see
https://live-agpest.pantheonsite.io/?pesttypes=yellow-bristle-grass
Social tagging: Chilean needle grass > Porina > Tasmanian grass grub beetle > Weed AlertIn summer-active grass infested pastures consider forage crops to selectively spray out summer-grasses before renewal.
Region: Northland, Auckland, BOP, Waikato, Taranaki
If your run-out pasture was infested with summer-active grass weeds last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations allowing better subsequent establishment of young clover.
Field horse tail is an invasive plant that is near impossible to destroy.
Region: Manawatu
Field horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors machines are clean and ask where the machines have been.
This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
Clover root weevils in pasture may reduce amount of N fixed by clover.
Region: All of NZ
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Ordering grass seed?
Region: All of NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Direct drilling?
Region: All of NZ
If direct drilling new pastures or crops check for slugs as these can devastate establishing seedlings. An application of slug pellets may be required, or control may be achieved by heavy stocking rates.
Use treated seed in black beetle prone areas to reduce adult numbers.
Region: Northland, Auckland, Bay of Plenty, Waikato
Northern North Island watch for clover flea damage to clover.
Region: Northland, Auckland, Bay of Plenty, Waikato
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining making the crop appear silver. Treat early if required to maximise effectiveness.
Pasture renewal required after grass grub/porina damage?
Region: Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
For pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for porina flights.
Region: Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
At the end of the month look for porina flights – indicated by large numbers being attracted to lights at night, as these can indicate when to adopt control measures at a later date if required.
Look for brassica springtails before sowing brassica crops.
Region: All of NZ
Place a white card or cloth on the soil surface and gently disturb the soil around it. This will cause the springtails to jump and land on it making them easier to see.
Be vigilant for new weeds which you have not seen before.
Region: All of NZ
In newly planted crops, scout for new weeds and weeds that have survived spraying with herbicides. Get these identified by sending photos to AgPest as they may be either a serious new incursion or have become resistant to herbicides. In either case it is important to get this sorted before they become established over large areas. Report weeds at www.agpest.co.nz/report
Are you noticing any weeds surviving after spraying?
Region: All of NZ
Weeds becoming resistant to herbicides is an increasing problem, we already have nodding thistle resistant to 2,4-D and MCPA and giant buttercup resistant to MCPA and flumetsulam. If you suspect you have resistant weeds and want them tested contact AgPest.
Watch out for Yellow Bristle Grass on the roadside, it is rapidly moving south.
Region: Canterbury, Marlborough, Nelson, Manawatu
Yellow bristle grass (YBG) is continuing to expand its range and is rapidly moving south into Manawatu and Canterbury. Watch for an upright grass with many compact, yellow-tinged seed heads appearing on the roadside. Take measures to stop it moving onto your farm. For more details see www.agpest.co.nz/?pesttypes=yellow-bristle-grass
Social tagging: Damage > Direct Drilling > Grass grub > Pasture > Porina > Yellow bristle grass
Pasture renewal required after grass grub/porina damage?
Region: Hawke’s Bay, Manawatu-Wanganui, Marlborough, Nelson/Tasman, Otago, Southland, Taranaki, Wellington,West Coast, Canterbury, Gisborne
For pastures badly affected by either grass grub or porina over winter and needing renewal consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Direct drilling new pasture?
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
If pasture establishment by direct drilling is going to be used check those pastures for pests, especially slugs and feeding grass grub as even low numbers can devastate young seedlings of pasture or crop plants.
If pasture is near the end of its life was infested with summer-active grass weeds (such as yellow bristle grass) ….
Region: Northland, Auckland, BOP, Waikato, Taranaki, Marlborough, Canterbury
If pasture is near the end of its life was infested with summer-active grass weeds (such as yellow bristle grass (YBG)) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
If your pasture is still strong but was infested with YBG consider locking it up for silage to reduce germination of YBG in the early summer. However, do not make it into hay as that will only spread the YBG.
Ordering grass seed?
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector at www.dairynzfvi.co.nz
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Clover root weevils in pasture may reduce amount of N fixed by clover.
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Northern North Island watch for clover flea damage to clover.
Region: Auckland, Waikato, Northland, Bay of Plenty
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Damage to pastures often becomes very obvious in winter.
Region: All of NZ
Generally it is too late to prevent production losses which have already occurred but pastures may be saved and long term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Porina and Grass grub damage is showing in lower North Island.
Region: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
The only option available to protect pasture now is insecticide.
Grass grub and porina damage will now be evident in most areas.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. At this time of year conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Porina damage in southern North Island from late moth flights may be apparent.
Region: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Porina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching control may only be warranted if it is required to preserve pasture plants.
Apply broadleaved weed herbicide to established pastures if needed once clover growth has slowed.
Region: All of NZ
Check established pastures for seedling broadleaved weeds such as nodding or winged thistle, ragwort or other troublesome weed and apply herbicide as necessary to the young weeds once clover growth has slowed.
Grass grub (yellow patches) and porina (bare ground) damage showing.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures. Porina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay, Otago
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. This pest is now established in Central Otago.
Make preparations for winter spraying of weeds if required.
Region: All of NZ
Make preparations for winter spraying of weeds if required. Scout paddocks and map infestations of weeds such as ragwort, thistles. Develop strategies for ongoing management of weedy areas, e.g. grazing, set-aside, spraying, nutrient or lime applications etc.
Social tagging: Grass grub > Porina > Tasmanian grass grub beetleGrass grub damage will be showing up by now.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
Grass grub damage is indicated by patches of pasture turning yellow and later becoming soft under foot. Pasture can be easily pulled back which is likely to reveal larvae feeding near the surface. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, except for caterpillars from late February/March flights in the North Island and the South Island West Coast which are still susceptible. In most cases porina control now needs to be by conventional insecticide.
After the drought most pastures will be open to infestations of winter weeds.
Region: All of NZ
Strengthen pastures by undersowing or opt for complete renewal. Either way manage broadleaved weeds by applying suitable herbicide 6-8 weeks after sowing.
Black beetle now infest large parts of the North Island with damaging populations.
Region: Northland, Auckland, BoP, Waikato
Black beetle now infest large parts of the North Island with damaging populations occurring as far south as coastal parts of Manawatu and Hawkes Bay. Endophytes such as AR37, and NEA2 deter the adult beetle from laying eggs in spring and thereby reduce larval numbers. To maximise the effects of endophyte, it is important that infection levels are high in ryegrass or tall fescue and that the pastures are not infested by other host grasses such as kikuyu or paspalum. See DairyNZ Pasture Renewal Guide
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay, Waikato, Manawatu, Canterbury, Otago
Unlike the NZ native grass grub, Tasmanian grass grub live underground and feed on herbage. Damage appears areas of poor pasture growth. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. This pest is now occurs throughout much of New Zealand.
Social tagging: AgPest > Black beetle > Broadleaved weed > Grass grub > Tasmanian grass grub beetleInspect young pastures for grass grub and porina.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
In grass grub or porina prone areas check pastures for damage. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft under foot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control, conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island are still susceptible. In most cases porina control now needs to be by conventional insecticide.
Direct drilling new pasture?
Region: All NZ
If pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Small weeds can be effectively controlled with herbicides which are soft on clovers but if the weeds get too large they can only be controlled with herbicides which also damage clovers.
Damage from black beetle larvae showing.
Region: Northland, Auckland, BoP, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Northern North Island watch for clover flea damage to clover.
Region: Northland, Auckland, BoP, Waikato
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness. See NZNovachem Agrichemical Manual.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay, Canterbury, Central Otago
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Velvetleaf and other weeds will be well into flowering now.
Region: All NZ
Velvetleaf and other weeds will be well into flowering now. If you notice a new weed get it identified. Any new plants that are appearing on your property or in your crops should be identified to a) assist you in managing it in the future, and b) to check that it is not a new incursion that should be dealt with on a wider scale. Send a clear photo(s) to AgPest to have it identified.
Social tagging: Black beetle > Clover flea > Direct Drilling > Grass grub > Porina > Tasmanian grass grub beetle > VelvetleafDirect drilling new pasture?
Region: All NZ
If pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Small weeds can be effectively controlled with herbicides which are soft on clovers but if the weeds get too large they can only be controlled with herbicides which also damage clovers.
Wanting to control Californian thistle?
Region: All NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Ordering grass seed?
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1,AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector on Dairy NZ’s Forage Value Index.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Late flights of porina occurring in lower North Island.
Region: Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington
Late flights of porina may occur in the North Island, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
In grass grub areas inspect 2 & 3 year old pastures for damaging levels of grubs.
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
In grass grub prone areas 2 and 3 year old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Northern North Island watch for clover flea damage to clover. and treat early if required to maximise effectiveness.
Region: Northland, Auckland, BoP, Waikato
Northern North Island watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Tasmanian grass grub damage may be showing.
Region: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Large numbers have been observed in southern Waikato.
Due to dry weather the pastures are very open.
Region: Northland, Auckland, BoP, Waikato
Due to dry weather the pastures are very open. There may be a flush of weeds after the first rain- treat if severe.
Pennyroyal can also become dominant after a drought and would need to be treated with 2,4-D early in spring if a problem.
Plantain moth numbers are building up.
Region: All NZ
Plantain moth numbers are building up and may increase dramatically after rain if warm conditions continue. Check with agchem reps. for insecticide options.
In 2016 velvetleaf was found in many fodder beet crops.
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Last year was a cool year and no velvetleaf was found in the SI but it was found at some NI sites. This year is much warmer and more velvetleaf is expected to germinate. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, visit MPI or AgPest online or contact your regional council.
Weeds can be spread via imported hay.
Region: Northland, Auckland, BoP, Waikato
If importing hay from other farms / regions be aware of unwanted weeds- many weed seeds can survive in and be spread via hay. Record the areas where hay has been fed out and regularly check these areas for new weeds after autumn and late spring rains- get rid of unwanted weeds before they become established! If you don’t recognise a weed get it identified.
Social tagging: Californian thistle > Direct Drilling > Grass grub > grass seed > imported hay > plantain moth > Porina > Tasmanian grass grub beetle > VelvetleafArgentine stem weevil is a significant threat to seedling grasses
Region: All of NZ
Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection.
In the northern North Island damage from black beetle larvae may be showing
Region: Northland, Auckland, BoP, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Second porina flight due
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
The early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight mid January to mid February is the optimal time to be applying diflubenzuron.
Ordering grass seed?
Region: All of NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Wanting to control Californian thistle?
Region: All of NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Watch for Tasmanian grass grub beetle flights.
Region: Gisborne, Hawkes Bay, Canterbury, Central Otago
Watch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Social tagging: AgPest > Argentine stem weevil > Californian thistle > Grass > Grass grub > Porina > Tasmanian grass grub beetleAphids, diamondback moth & white butterfly caterpillars in brassica crops increasing in numbers.
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Watch for plantain caterpillars and moths
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui
Plantain moths and caterpillars populations maybe high or building up. Apply insecticide early to prevent damage occurring
In the northern North Island damage from black beetle larvae may be showing
Region: Northland, Auckland, BoP, Waikato
In the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Watch for Tasmanian grass grub beetle flights
Region: Gisborne, Hawkes Bay, Canterbury, Central Otago
Watch for Tasmanian grass grub beetle flights, large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Flights of porina moths
Region:Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast,
Otago, Southland
The early flight of porina moths has passed but the second significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Argentine stem weevils will increase in significance over summer
Region: All of NZ
Argentine stem weevils increase in significance over summer. Be aware that seedling grasses, even those infected with endophyte, are very susceptible to damage from this pest if numbers are high. This also applies to cereal and maize crops. Coated seed or pre-emergence insecticide application can prevent damage.
Clover root weevil damage
Region: All of NZ
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
If you have grown fodder beet over the past 3 years
Region: All of NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Apply herbicides to yellow bristle grass before seed heads ripen
Region: Northland, Auckland, Waikato, Bay of Plenty, Taranaki
Apply herbicides to yellow bristle grass before seed heads ripen. Avoid moving stock from infested to clean paddocks – seeds can survive in dung.
Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds can survive in hay. In contrast, yellow bristle grass seeds are highly unlikely to survive in well-made silage and wrapped baleage.
Make note of porina flights
Region: Waikato, Hawke’s Bay, Taranaki, Whanganui, Manawatū, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Be vigilant for velvetleaf
Region: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: AgPest > Biosecurity > Fodder beet seed > Ministry for Primary Industries > MPI > Porina > Summer-active grass > Unwanted Organism > Velvetleaf > Weed Alert > Yellow bristle grassCheck sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish-purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed/hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately. Learn more on AgPest.
Tasmanian grass grub flights occurring
Region: All NZ
Tasmanian grass grub beetle flights occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Treat aphids, diamondback moth and white butterfly caterpillars in brassica crops
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures, these can increase quickly. Treating these pests before high numbers occur will provide the greatest economic return.
Clover root weevil will be very obvious – manage carefully
Region: All NZ
Clover root weevil will be very obvious in most areas. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
Social tagging: AgPest > Aphids > Chilean needle grass > Clover root weevil > Diamondback moth > Invasive > Nitrogen > Pasture > Tasmanian grass grub beetle > White butterfly
Check sunny slopes for Chilean needle grass
Region: All NZ, except West Coast of the South Island
Chilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found here on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Watch for porina flights
Region: Lower North Island, South Island
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Tasmanian grass grub beetle flights occurring
Region: All NZ
Tasmanian grass grub beetle flights are occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Social tagging: AgPest > Chilean needle grass > Grass grub > Invasive > Pest Alert > Porina > Weed AlertCheck sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish-purple colour of the seed heads when they first emerge.
Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes, but may be present in contaminated stock feed/hay.
If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Clover root weevil present, extra N may be needed in pastures
Region: All NZ
Clover root weevil will be very obvious in most areas –U shaped notches at the edge of clover leaves show adults are present. The presence of larvae may be indicated by the pasture appearing nitrogen deficient. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
Take Argentine stem weevil into account when establishing crops or pasture
Region: All North Island
Argentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment. Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Social tagging: AgPest > Argentine stem weevil > Biosecurity > Chilean needle grass > Clover root weevil > crops > Invasive > Nitrogen > Pasture > Weed AlertWatch for clover flea damage & treat early
Region: Northland, South Auckland, Waikato, Bay of Plenty
In the Northern North Island watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining, making the crop appear silver. Treat early if required to maximise effectiveness.
Pasture renewal required after grass grub/porina damage?
Region: Lower North Island, South Island
For pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for porina flights
Region: Lower North Island, South Island
At the end of the month look for porina flights – indicated by large numbers being attracted to lights at night, as these can indicate when to adopt control measures at a later date if required.
Check for brassica springtails before sowing brassica crops
Region: All NZ
Look for brassica springtails before sowing brassica crops. Place a white card or cloth on the soil surface and gently disturb the soil around it. This will cause the springtails to jump and land on it making them easier to see.
Herbicide-resistant weeds becoming a problem
Region: All NZ
Weeds becoming resistant to herbicides is an increasing problem, we already have nodding thistle resistant to 2,4-D and MCPA and giant buttercup resistant to MCPA and flumetsulam. If you suspect you have resistant weeds and want them tested contact AgPest.
Social tagging: AgPest > brassica > Brassica springtails > Clover flea > Damage > Grass grub > Pasture > Pasture Damage > Porina > SprayingConsider forage crops to selectively spray out summer grasses before renewal
Region: Northland, Auckland, Bay of Plenty, Waikato, Taranaki
If your run-out pasture was infested with summer-active grass weeds last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations allowing better subsequent establishment of young clover.
Prevent the establishment of field horsetail
Region: Manawatū
Field horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors’ machines are clean and ask where the machines have been.
This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
Clover root weevils in pasture may reduce N fixing
Region: All NZ
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Select endophyte when ordering grass seed
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Look for slugs when direct drilling
Region: All NZ
If direct drilling new pastures or crops check for slugs as these can devastate establishing seedlings. An application of slug pellets may be required, or control may be achieved by heavy stocking rates.
Sow treated seed in black beetle-prone areas
Region: Northland, Auckland, Bay of Plenty, Waikato
Use treated seed in black beetle prone areas to reduce adult numbers.
Social tagging: AgPest > Argentine stem weevil > Black beetle > Clover root weevil > Direct Drilling > Endophyte > Field horsetail > Invasive > Pasture Damage > Porina > Slugs > Summer-active grassOrdering grass seed? Select endophyte.
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector, Forage Value Index (FVI)
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Compensatory N applications may be needed due to clover root weevils
Region: All NZ
In established pastures with high levels of clover root weevil, the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Watch for clover flea damage and treat early
Region: Northland, Auckland, Waikato, Bay of Plenty
In Northern North Island watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: AgPest > Clover > Clover flea > Clover root weevil > Endophyte > Pasture > Pasture Damage > Pest
Consider direct drilling to renew pasture after grass grub/porina damage
Region: Taranaki, Gisborne, Hawke’s Bay, Manawatū, Whanganui, Wellington, Marlborough, Nelson-Tasman, West Coast, Canterbury, Otago, Southland.
For pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for pests, esp. slugs & feeding grass grubs when direct drilling new pasture
Region: All NZ
If pasture establishment by direct drilling is going to be used, check those pastures for pests, especially slugs and feeding grass grub as even low numbers can devastate young seedlings of pasture or crop plants.
Pasture infested with Yellow bristle grass? Consider forage crops.
Region: Northland, Auckland, Bay of Plenty, Waikato.
If your run-out pasture was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
Social tagging: AgPest > Direct Drilling > Grass > Grass grub > Porina > Slugs > Weed Alert > Yellow bristle grass
Pest damage showing in pasture
Region: All NZ
Damage to pastures often becomes very obvious in winter. Generally, it is too late to prevent production losses which have already occurred but pastures may be saved and long term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Porina and grass grub damage showing in the lower North Island
Region: Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington
Porina and grass grub damage is showing in lower North Island. The only option available to protect pasture now is insecticide.
Social tagging: AgPest > Grass grub > Pasture Damage > PorinaTasmanian grass grub damage may be showing
Region: Gisborne, Hawke’s Bay.
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching control may only be warranted if it is required to preserve pasture plants.
Check for seedling broadleaved weeds
Region: All NZ
Check established pastures for seedling broadleaved weeds such as nodding or winged thistle, ragwort or other troublesome weed and apply herbicide as necessary to the young weeds once clover growth has slowed.
Social tagging: AgPest > Broadleaved weed > Pasture Damage > Pest Alert > Tasmanian grass grub > Weed AlertGrass grub and porina damage showing
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatū Whanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year, these patches become soft underfoot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. At this stage of the year, conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Porina damage from late flights may be apparent in lower North Island
Region: Hawke’s Bay, Taranaki, Manawatū Whanganui, Wairarapa, Wellington
Porina damage from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Social tagging: AgPest > Grass grub > Pasture Damage > PorinaGrass grub and porina damage showing
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year, these patches become soft underfoot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures. Porina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Tasmanian grass grub damage may be showing
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Make preparations for winter weed spraying
Region: All NZ
Make preparations for winter spraying of weeds, if required. Scout paddocks and map infestations of weeds such as ragwort, thistles. Develop strategies for ongoing management of weedy areas, e.g. grazing, set-aside, spraying, nutrient or lime applications etc.
Social tagging: Damage > Grass > Grass grub > Pasture Damage > Pest Alert > Porina > Tasmanian grass grub > Weed AlertInspect young pastures for grass grub & porina
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub or porina prone areas check pastures for damage which is now showing. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft underfoot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island and the South Island West Coast are still susceptible.
In most cases, porina control now needs to be by conventional insecticide.
Manage broadleaved weeds by applying herbicide
Region: All NZ.
Check new pastures and apply herbicide as necessary to control broadleaved weeds (6-8 weeks after establishment).
Social tagging: Grass > Grass grub > Pest Alert > Porina > Weed AlertCheck pastures & assess Tasmanian grass grub damage
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Notice a new weed? It could be Velvetleaf – be sure to have it identified
Region: All NZ
Velvetleaf and other weeds will be well into flowering now. If you notice a new weed get it identified. Any new plants that are appearing on your property or in your crops should be identified to a) assist you in managing it in the future, and b) to check that it is not a new incursion that should be dealt with on a wider scale. Send a clear photo(s) to AgPest to have it identified.
Social tagging: AgPest > Biosecurity > Damage > Pest Alert > Tasmanian grass grub > Unwanted Organism > Velvetleaf > Weed Alert
To all of the essential workers in our primary industries – thank you for your work keeping our country fed and moving.
While the country is on lockdown, pests and weeds certainly aren’t, so AgPest will continue to send alerts twice per month.
Velvetleaf will be flowering now – notice a new weed? Get it identified.
Region: All NZ
Velvetleaf and other weeds will be well into flowering now. If you notice a new weed get it identified. Any new plants that are appearing on your property or in your crops should be identified to a) assist you in managing it in the future, and b) to check that it is not a new incursion that should be dealt with on a wider scale.
Please send a clear photo(s) to AgPest to have it identified.
Inspect young pastures for grass grub and porina
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub or porina prone areas, check pastures for damage.
Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft underfoot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control, conventional insecticide (diazinon) may be the only recourse.
It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island are still susceptible. In most cases, porina control now needs to be by conventional insecticide.
Damage from black beetle larvae showing
Region: Northland, Auckland, Bay of Plenty, Waikato.
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this.
Adults are deterred by some endophyte-infected grasses which will reduce egg-laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Watch for and treat clover flea damage
Region: Northland, Auckland, Bay of Plenty, Waikato.
In Northern NZ, watch for clover flea damage to clover and treat early if required to maximise effectiveness. See NZNovachem Agrichemical Manual.
Social tagging: Black beetle > Clover flea > Grass grub > Pest Alert > Porina > Unwanted Organism > Velvetleaf > Weed Alert
Velvetleaf is flowering – be vigilant to eliminate this invasive weed
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Last year was a cool year and no velvetleaf was found in the SI but it was found at some NI sites. This year is much warmer and more velvetleaf is expected to germinate. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, visit MPI or AgPest online or contact your regional council.
Watch for clover flea damage
Region: Northland, Auckland, Bay of Plenty, Waikato
In the Northern North Island, watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Tasmanian grass grub damage may be showing
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Large numbers have been observed in southern Waikato.
Flush of weeds expected after dry Summer
Region: Northland, Auckland, Bay of Plenty, Waikato
Due to dry weather, the pastures are very open. There may be a flush of weeds after the first rain – treat if severe.
Pennyroyal can also become dominant after a drought and would need to be treated with 2,4-D early in spring if a problem.
Plantain moth numbers building
Region: All NZ
Plantain moth numbers are building up and may increase dramatically after rain if warm conditions continue. Check with agchem reps for insecticide options.
Weeds can be spread via imported hay – check feed-out areas
Region: Northland, Auckland, Bay of Plenty, Waikato
If importing hay from other farms/regions be aware of unwanted weeds- many weed seeds can survive in and be spread via hay. Record the areas where hay has been fed out and regularly check these areas for new weeds after autumn and late spring rains- get rid of unwanted weeds before they become established! If you don’t recognise a weed get it identified.
Social tagging: Clover flea > Fodder beet seed > Invasive > Pest Alert > Tasmanian grass grub > Unwanted Organism > Velvetleaf > Weed AlertBe vigilant for Velvetleaf
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Last year was a cool year and no velvetleaf was found in the South Island but it was found at some North Island sites. This year is much warmer and more velvetleaf is expected to germinate.
Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, visit MPI or AgPest online or contact your regional council.
Direct drilling new pasture? Look for slugs and grass grub.
Region: All NZ
If pasture establishment by direct drilling is going to be used, check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Control Californian thistle by mowing in the rain
Region: All NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Ordering grass seed? Select endophyte
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1,AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector on Dairy NZ’s Forage Value Index.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Late flights of porina
Region: Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington
Late flights of porina may occur in the North Island. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
Inspect 2- and 3-year-old pastures for grass grub
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub prone areas 2- and 3-year-old pastures should be inspected to determine if potentially damaging levels are present.
Early treatment will offer the most protection and maximise returns from the cost of intervention.
Social tagging: AgPest > Biosecurity > Californian thistle > Damage > Direct Drilling > Endophyte > Fodder beet seed > Grass grub > Invasive > Ministry for Primary Industries > MPI > Pasture Damage > Pest Alert > Porina > Slugs > Unwanted Organism > Velvetleaf
Wanting to control Californian thistle? Mow in the rain.
Region: All NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Watch for Tasmanian grass grub beetle flights.
Region: Gisborne, Hawke’s Bay
Watch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Clover root weevil damage may be obvious but not significant.
Region: All NZ
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent.
Include non-clover break crop for pasture renewal after Clover root weevil.
Region: All NZ
Clover root weevil: pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover free break crop provides a temporary weevil free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Inspect 2-3 year-old pastures for damaging levels of grass grub
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub prone areas 2 and 3-year-old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer the most protection and maximise returns from the cost of intervention.
Watch for clover flea damage and treat early.
Region: Northland, Auckland, Bay of Plenty, Waikato.
In the North or the North Island, watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Remain vigilant for Velvetleaf
Region: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: AgPest > Californian thistle > Clover flea > Clover root weevil > Grass grub > Pest Alert > Tasmanian grass grub > Unwanted Organism > Velvet Leaf > Velvetleaf > Weed AlertDelay sowing to avoid Argentine stem weevil
Region: All NZ
Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection
Damage from black beetle larvae may be showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte-infected grasses which will reduce egg-laying and larval numbers. See DairyNZ Pasture Renewal Guide
Second flight of porina expected in Sth Is.
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Whanganui, Manawatū, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
The early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight mid-January to mid-February is the optimal time to be applying diflubenzuron.
Ordering grass seed? Select endophyte.
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: AgPest > Argentine stem weevil > Black beetle > Endophyte > Pasture > Pest Alert > Porina > Weed AlertTreat aphids, diamondback moth & white butterfly before numbers rise
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures, these can increase quickly. Treating these pests before high numbers occur will provide the greatest economic return.
Watch for plantain caterpillars and moths
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui.
Plantain moths and caterpillars populations may be high or building up. Apply insecticide early to prevent damage occurring.
Damage from black beetle larvae may be showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte-infected grasses which will reduce egg-laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Watch for Tasmanian grass grub beetle flights
Region: Gisborne, Hawke’s Bay
Watch for Tasmanian grass grub beetle flights, large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Time to apply diflubenzuron for porina control
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Whanganui, Manawatū, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
The early flight of porina moths has passed but the second significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Social tagging: Aphid > Black beetle > Diamondback moth > Pest Alert > Porina > Tasmanian grass grub beetleTitle in bold
Region in italics
First pest/weed in standard paragraph text
Divide with the line then enter the next one.
Social tagging: AgPestApply herbicides to Yellow bristle grass
Region: Northland, Auckland, Waikato, Bay of Plenty, Taranaki
Apply herbicides to yellow bristle grass before seed heads ripen. Avoid moving stock from infested to clean paddocks – seeds can survive in dung.
Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds can survive in hay. In contrast, yellow bristle grass seeds are highly unlikely to survive in well-made silage and wrapped baleage.
Note Porina flights from now on
Region: Waikato, Bay of Plenty, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Be vigilant for Velvetleaf
Region: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property, you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, go to MPI or AgPest, or contact your regional council.
Social tagging: AgPest > Fodder beet seed > Ministry for Primary Industries > MPI > Pest Alert > Porina > Unwanted Organism > Velvetleaf > Weed AlertTasmanian grass grub beetle flights occurring
Region: All NZ
Tasmanian grass grub beetle flights occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Brassica crop pests increasing in number
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures, these can increase quickly. Treating these pests before high numbers occur will provide the greatest economic return.
Check sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish-purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed/hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Clover root weevil present in most areas
Region: All NZ
Clover root weevil will be very obvious in most areas. While control is generally not an option, careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over-grazed.
Social tagging: AgPest > Chilean needle grass > Clover root weevil > Pest Alert > Tasmanian grass grub beetle > Weed AlertCheck sunny slopes for Chilean needle grass
Region: All NZ EXCEPT West Coast of South Island
Chilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found here on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Tasmanian grass grub beetle flights occurring
Region: All NZ
Tasmanian grass grub beetle flights occurring. This pest appears to be spreading and may appear in areas where it has not previously been seen. e.g. It is now present in Cromwell. The significance of this is not yet known. New observations can be reported to colin.ferguson@agresearch.co.nz
Social tagging: AgPest > Chilean needle grass > Pest Alert > Tasmanian grass grub beetle > Weed AlertClover root weevil present, don’t overgraze clover
Region: All NZ
Clover root weevil will be very obvious in most areas – U-shaped notches at the edge of clover leaves show adults are present. The presence of larvae may be indicated by the pasture appearing nitrogen deficient. While control is generally not an option, careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
Consider Argentine stem weevil when choosing pasture/crop
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatū, Whanganui, Wellington.
Argentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment. Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Check sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish-purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed/hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Note porina flights
Region: Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Social tagging: AgPest > Argentine stem weevil > Chilean needle grass > Clover root weevil > Pest Alert > Weed AlertReduce adult black beetle numbers
Region: Northland, Auckland, Waikato, Bay of Plenty
Sow treated seed in black beetle-prone areas to reduce adult numbers.
Watch for clover flea damage & treat early
Region: Northland, Auckland, Waikato, Bay of Plenty
Watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining, making the crop appear silver. Treat early if required to maximise effectiveness.
Consider direct drilling to renew pasture after grass grub damage
Region: Taranaki, Manawatū-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
For pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for porina flights
Region: Taranaki, Manawatū-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
At the end of the month look for porina flights – indicated by large numbers being attracted to lights at night, as these can indicate when to adopt control measures at a later date if required.
Check for brassica springtails before sowing crops
Region: All NZ
Look for brassica springtails before sowing brassica crops. Place a white card or cloth on the soil surface and gently disturb the soil around it. This will cause the springtails to jump and land on it making them easier to see.
Social tagging: AgPest > Black beetle > Clover flea > Pest Alert
Consider forage crops to combat summer grasses
Region: Northland, Auckland, Waikato, Bay of Plenty
If your run-out pasture was infested with summer-active grass weeds last Summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations allowing better subsequent establishment of young clover.
Prevent establishment of invasive weed Field horse tail
Region: Manawatū
Field horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors’ machines are clean and ask where the machines have been.
This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
Clover root weevils may reduce N fixed by clover
Region: All NZ
In established pastures with high levels of clover root weevil, the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Ordering grass seed? Select endophyte.
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Look for slugs when direct drilling
Region: All NZ
If direct drilling new pastures or crops check for slugs as these can devastate establishing seedlings. An application of slug pellets may be required, or control may be achieved by heavy stocking rates.
Social tagging: Argentine stem weevil > Black beetle > Clover root weevil > Endophyte > Field horsetail > Grass > Pest Alert > Porina > Slugs > Summer-active grass > Weed Alert
Select endophyte when ordering grass seed
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the DairyNZ Cultivar Selector.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Compensatory N applications may be necessary
Region: All NZ
In established pastures with high levels of clover root weevil, the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Watch for clover flea damage to clover
Region: Northland, Auckland, Bay of Plenty, Waikato.
Check for clover flea damage to clover and treat early if required, to maximise effectiveness.
Social tagging: Argentine stem weevil > Black beetle > Clover > Clover flea > Clover root weevil > Endophyte > Grass > Pasture > Pasture Renewal Guide > Pest Alert
Consider direct drilling for grass grub/porina pasture damage
Region: Gisborne, Hawke’s Bay, Manawatu, Taranaki, Whanganui, Wellington, Marlborough, Nelson-Tasman, Canterbury, West Coast, Otago, Southland.
For pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for pests when direct drilling new pasture
Region: All NZ
If pasture establishment will be by direct drilling, check those pastures for pests, especially slugs and feeding grass grub as even low numbers can devastate young seedlings of pasture or crop plants.
Consider forage crops to control Summer-grasses
Region: Northland, Auckland, Bay of Plenty, Waikato
If your run-out pasture was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
Social tagging: AgPest > Damage > Direct Drilling > Grass grub > Porina > Weed Alert
Pest damage showing in pastures
Region: All NZ
Damage to pastures often becomes very obvious in winter. Generally, it is too late to prevent production losses which have already occurred, but pastures may be saved and long term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Protect pasture from porina and grass grub
Region: Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington
Porina and grass grub damage is showing in lower North Island. The only option available to protect pasture now is insecticide.
Social tagging: AgPest > Grass grub > Pasture Damage > Pest > Pest Alert > PorinaCheck pastures for Tasmanian grass grub damage
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching, control may only be warranted if it is required to preserve pasture plants.
Look for seedling broadleaved weeds
Region: All
Check established pastures for seedling broadleaved weeds such as nodding or winged thistle, ragwort or other troublesome weed and apply herbicide as necessary to the young weeds once clover growth has slowed.
Social tagging: Broadleaved weed > Clover > Ragwort > Tasmanian grass grub > ThistleAct now to prevent long term loss of pasture quality
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year, these patches become soft underfoot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Porina damage in lower Nth Is may be apparent
Region: Hawke’s Bay, Taranaki, Manawatū, Whanganui, Wairarapa, Wellington.
Porina damage from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Social tagging: AgPest > Grass grub > Pasture Damage > Pest > Pest Alert > PorinaInsecticide may prevent long term pasture loss to grass grub and porina
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year, these patches become soft underfoot and are prone to pugging.
Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures. Porina damage, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights, may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Check pastures for Tasmanian grass grub damage
Region: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures, particularly around stock camps, and assess numbers to determine if insecticidal control is warranted.
Make preparations for winter spraying of weeds
Region: All NZ
Make preparations for winter spraying of weeds if required. Scout paddocks and map infestations of weeds such as ragwort, thistles. Develop strategies for ongoing management of weedy areas, e.g. grazing, set-aside, spraying, nutrient or lime applications etc.
Social tagging: AgPest > Grass grub > Pest Alert > Porina > Tasmanian grass grub beetle > Weed AlertDamage from grass grub and porina now showing
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub or porina prone areas, check pastures for damage which is now showing. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft underfoot.
Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground.
Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control, conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island and the South Island West Coast are still susceptible. In most cases, porina control now needs to be by conventional insecticide.
Time for broadleaved weed herbicide
Region: All NZ
Check new pastures and apply herbicide as necessary to control broadleaved weeds (6-8 weeks after establishment).
Damage from black beetle larvae showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately, little can be done to prevent this. Adults are deterred by AR37, Endo5 & NEA2 endophyte-infected grasses, which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Tasmanian grass grub damage may be showing
Region: Gisborne, Hawkes Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures, particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Social tagging: AgPest > Black beetle > Damage > Endophyte > Grass grub > Pasture Damage > PorinaTreat clover flea damage early
Region: Northland, Auckland, Bay of Plenty, Waikato
Watch for clover flea damage to clover and treat early if required to maximise effectiveness. See NZNovachem Agrichemical Manual.
Tasmanian grass grub damage may be showing
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Social tagging: AgPest > Clover flea > Pasture Damage > Pest Alert > Tasmanian grass grub beetleCheck pasture for grass grub or porina damage
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub or porina prone areas check pastures for damage. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft underfoot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling or high stocking rates may provide some level of grass grub control, conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although caterpillars from late February/March flights in the North Island are still susceptible. In most cases, porina control now needs to be by conventional insecticide.
Black beetle larvae damage may be showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Social tagging: AgPest > Black beetle > Grass grub > Pasture Damage > Pest Alert > PorinaWatch for clover flea damage
Region: Northland, Auckland, Bay of Plenty, Waikato
Northern North Island watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Check pastures for Tasmanian grass grub damage
Region: Gisborne
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Large numbers have been observed in southern Waikato.
Dry weather leads to open pastures
Region: Northland, Auckland, Bay of Plenty, Waikato
Due to dry weather, the pastures are very open. There may be a flush of weeds after the first rain- treat if severe.
Pennyroyal can also become dominant after a drought and would need to be treated with 2,4-D early in spring if a problem.
Plantain moth numbers building
Region: All NZ
Plantain moth numbers are building up and may increase dramatically after rain if warm conditions continue. Check with agchem reps. for insecticide options.
Continued vigilance with velvetleaf
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Last year was a cool year and no velvetleaf was found in the SI but it was found at some NI sites. This year is much warmer and more velvetleaf is expected to germinate. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66, visit MPI or AgPest online or contact your regional council.
Check feed-out areas for weeds
Region: Northland, Auckland, Bay of Plenty, Waikato
If importing hay from other farms/regions, be aware of unwanted weeds – many weed seeds can survive in and be spread via hay. Record the areas where hay has been fed out and regularly check these areas for new weeds after autumn and late spring rains- get rid of unwanted weeds before they become established! If you don’t recognise a weed get it identified.
Social tagging: AgPest > Biosecurity > Clover flea > Invasive > Ministry for Primary Industries > Tasmanian grass grub beetle > Unwanted Organism > Velvet Leaf > VelvetleafDirect drilling new pasture? Watch for slugs and grass grub.
Region: All NZ
If pasture establishment by direct drilling is going to be used, check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Control Californian thistle by mowing in rain
Region: All NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Select endophyte when ordering grass seed
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1, AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector on Dairy NZ’s Forage Value Index.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Late flights of porina occurring in lower North Island
Region: Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington
Late flights of porina may occur in the North Island, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
Inspect grass grub areas for damaging levels
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington, Nelson, Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub prone areas 2 and 3-year-old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Social tagging: Argentine stem weevil > Black beetle > Californian thistle > Damage > Endophyte > Grass grub > Pasture > Pasture Damage > Pest Alert > Slugs > Weed Alert
Watch for Tasmanian grass grub beetle flights
Region: Gisborne, Hawkes Bay
Watch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Clover root weevil damage becoming obvious
Region: All NZ
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent.
Pasture renewal should incorporate non-clover break to combat Clover root weevil
Region: All NZ
Clover root weevil. Pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover-free break crop provides a temporary weevil-free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Early treatment of grass grum will maximise returns
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In grass grub prone areas 2- and 3-year-old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer the most protection and maximise returns from the cost of intervention.
Watch for clover flea damage in the North of NZ
Region: Northland, Auckland, Bay of Plenty, Waikato.
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness. See NZ Novachem Agrichemical Manual.
Be vigilant for Velvetleaf
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Biosecurity > Clover > Clover flea > Clover root weevil > Grass grub > Ministry for Primary Industries > MPI > Pasture > Pasture Damage > Pest > Pest Alert > Tasmanian grass grub beetle > Unwanted Organism > Velvet Leaf > Velvetleaf > Weed > Weed Alert
Delay sowing pasture until early March, if possible
Region: All NZ
Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection.
Black beetle larvae damage may be showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte-infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Second flight of porina moths expected
Region: Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki-Manawatu, Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
The early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight mid-January to mid-February is the optimal time to be applying diflubenzuron.
Ordering grass seed? Select endophyte.
Region: All NZ
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Want to control Californian thistle?
Region: All NZ
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Social tagging: AgPest > Argentine stem weevil > Black beetle > Californian thistle > Damage > Endophyte > Grass > Pasture > Pasture Damage > Pest > Pest Alert > Weed AlertBe vigilant for velvetleaf
Region: All NZ
In 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Watch for second porina moth flights
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatu-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
The early flight of porina moths has passed but the second significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Argentine stem weevils increasingly significant in Summer
Region: All NZ
Argentine stem weevils increase in significance over summer. Be aware that seedling grasses, even those infected with endophyte, are very susceptible to damage from this pest if numbers are high. This also applies to cereal and maize crops. Coated seed or pre-emergence insecticide application can prevent damage.
Clover root weevil adults abundant
Region: All NZ
Clover root weevil adults are abundant and damage to clover leaves will be obvious in most areas. Unless severe this is not significant damage and does not mean the biocontrol agent is absent.
Social tagging: AgPest > Argentine stem weevil > Biosecurity > Clover root weevil > Endophyte > Ministry for Primary Industries > Pest > Pest Alert > Unwanted Organism > Velvet Leaf > Velvetleaf > Weed > Weed Alert
Happy New Year!
Watch for aphids, diamondback moth & white butterfly caterpillars in brassica crops.
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return. But check that natural predators and parasites are not already providing control.
Plantain moths and caterpillar populations may be high
Region: Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatu-Whanganui.
Plantain moths and caterpillars populations may be high or building up. Apply insecticide early to prevent damage occurring.
Black beetle larvae damage maybe showing
Region: Northland, Auckland, Bay of Plenty, Waikato
In the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte-infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Watch for Tasmanian grass grub beetle flights
Region: Gisborne, Hawke’s Bay
Watch for Tasmanian grass grub beetle flights, large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Social tagging: Black beetle > brassica > Damage > Grass grub > Pasture Damage > Pest Alert > Tasmanian grass grub beetle
Be alert for yellow bristle grass
Region: Northland, Auckland, Waikato, BOP, Taranaki
Apply herbicides to yellow bristle grass before seed heads ripen. Avoid moving stock from infested to clean paddocks – seeds can survive in dung.
Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds survive in hay. In contrast, yellow bristle grass seeds do not survive in well-made silage and wrapped baleage.
Look for porina flights
Region: Waikato, Hawkes Bay, Taranaki, Manawatu-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Remain vigilant for velvetleaf
Region: All NZ
Velvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is a declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or AgPest, or contact your regional council.
Social tagging: AgPest > Fodder beet seed > Invasive > Ministry for Primary Industries > MPI > Porina > Unwanted Organism > Velvetleaf
Watch for Aphids, diamondback moth & white butterfly on brassica crops
Region: All NZ
Keep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Check sunny slopes for Chilean needle grass
Region: All NZ
Chilean needle grass will become evident in pastures in December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed/hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Clover root weevil present in most areas
Region: All NZ
Clover root weevil will be obvious in most areas as new adults emerge. This does not mean biocontrol is not working, the wasp will also increase in numbers. Other control is generally not an option, but careful management of clover will help maintain pasture quality. Additional nitrogen can be applied to pastures if required and clover should not be overgrazed.
Social tagging: AgPest > Chilean needle grass > Clover root weevil > Damage > Nitrogen > Pasture > Pest Alert > Weed Alert
Check sunny slopes for Chilean needle grass throughout Nov/Dec
Region: All except West Coast of South Island
Chilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found here on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Social tagging: AgPest > Chilean needle grass > Weed AlertConsider Argentine stem weevil in pasture/crop establishment
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu-Whanganui, Wellington.
Argentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment. Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses (even those infected with endophyte), cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Keep an eye out for porina flights
Region: Taranaki, Manawatu-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Reduce adult black beetle numbers
Region: Northland, Auckland, Bay of Plenty, Waikato
Sow treated seed in black beetle prone areas to reduce adult numbers
Watch for clover flea damage to clover
Region: Northland, Auckland, Bay of Plenty, Waikato
Watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining, making the crop appear silver. Treat early if required to maximise effectiveness.
Spring pasture renewal or renovation?
Region: Taranaki, Manawatu, Whanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
For spring sowing or renovating pastures badly affected by grass grub or porina over winter, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long-term population regulation. Leave sowing as late as possible as both pests may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Look for porina flights
Region: Taranaki, Manawatu, Whanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
At the end of the month look for porina flights – indicated by large numbers being attracted to lights at night, as these can indicate when to adopt control measures at a later date if required.
Look for brassica springtails
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu, Whanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland
Look for brassica springtails before sowing brassica crops. Place a white card or cloth on the soil surface and gently disturb the soil around it. This will cause the springtails to jump and land on it making them easier to see.
Social tagging: AgPest > Black beetle > brassica > Clover flea > Clover root weevil > crops > Damage > Direct Drilling > Grass grub > Pasture > Pasture Damage > Pest Alert > Porina
Consider growing forage crops to combat summer grasses.
Region: Northland, Auckland, Bay of Plenty, Waikato, Taranaki.
If your run-out pasture was infested with summer-active grass weeds last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations allowing better subsequent establishment of young clover.
Prevent establishment of Field horsetail.
Region: Manawatu
Field horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors’ machines are clean and ask where the machines have been.
This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
Clover root weevil may reduce N fixing.
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawkes Bay, Taranaki, Manawatu Wanganui, Wellington, Nelson Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Ordering grass seed for Spring sowing?
Region: Nelson/Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
If ordering grass seed for spring sowing, select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: AgPest > Argentine stem weevil > Black beetle > Clover root weevil > Endophyte > Field horsetail > Grass > Pasture > Pasture Damage > PorinaClover root weevil an issue?
Region: Northland, Auckland, Bay of Plenty, Waikato, Gisborne, Hawke’s Bay, Taranaki, Manawatu-Whanganui, Wellington, Nelson-Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
If clover root weevil is an issue in your area, pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover-free break crop provides a temporary weevil-free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Watch for clover flea damage
Region: Northland, Auckland, Waikato, Bay of Plenty
Watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Clover > Clover flea > Clover root weevil > Pasture > Pasture Damage > Pest > Pest Alert
Spring pasture renewal or renovation after grass grub/porina damage?
Region: Gisborne, Hawke’s Bay, Taranaki, Manawatu, Whanganui, Wellington, Marlborough, Nelson/Tasman, West Coast, Canterbury, Otago, Southland
For spring sowing or renovating pastures badly affected by grass grub or porina over winter consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long-term population regulation. Leave sowing as late as possible as both pests, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Yellow bristle grass? Consider forage crops.
Region: Northland, Auckland, Bay of Plenty, Waikato
If your run-out pasture was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
Select endophyte for spring sowing.
Region: Nelson/Tasman, Marlborough, Canterbury, West Coast, Otago, Southland.
If ordering grass seed for spring sowing select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the Dairy NZ cultivar selector.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: AgPest > Direct Drilling > Endophyte > Grass grub > Pasture Damage > Pest Alert > Porina > Weed AlertPest damage showing – treatment may aid recovery
Region: All NZ
Damage to pastures often becomes very obvious in winter. Generally, it is too late to prevent production losses which have already occurred, but pastures may be saved and long-term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Porina & grass grub damage evident
Region: Lower North Island
Porina and grass grub damage is showing in lower North Island. The only option available to protect pasture now is insecticide.
Social tagging: AgPest > Pasture Damage > Pest > Pest Alert
Check for broadleaved weeds
Region: All NZ
Check established pastures for broadleaved weeds and apply herbicide as necessary once clover growth has slowed.
Check for grass grub damage
Region: Gisborne, Hawke’s Bay
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching control may only be warranted if it is required to preserve pasture plants.
Welcome back to AgPest alerts.
After a longer-than-expected break, AgPest alerts are back with a new look and will arrive in your inbox twice-monthly to help with weed and pest related issues.
Thank you for your patience.
Grass grub and porina damage becoming evident
Grass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year, these patches become soft underfoot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Watch for porina damage in Mid/Lower North Island
Porina damage (especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu) from caterpillars, arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Hi there. Thanks for being an AgPest subscriber.
We’re moving to a different email provider for our AgPest alerts and while this changeover happens, we’ve combined three alerts for early March into one digest, covering three issues: slugs & grass grubs, Californian thistle and selection of grass seed with suitable endophytes.
We’re expecting to resume normal service from 15th March.
Slugs & grass grub
If pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Mowing Californian thistle
Mowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Selecting suitable endophytes
When ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1,AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the Dairy NZ cultivar selector.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: AgPest > Argentine stem weevil > Black beetle > Californian thistle > Direct Drilling > Endophyte > Grass grub > Pasture > Pasture Damage > Pest Alert > Porina > Seedlings > Slugs > Weed AlertLate flights of porina may occur in the North Island, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
Social tagging: Pest Alert > PorinaIn 2016 velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date, more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly, there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvetleaf is a declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: AgPest > Fodder beet seed > Invasive > Ministry for Primary Industries > MPI > Unwanted Organism > Velvetleaf > Weed AlertIn Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Clover > Clover flea > Pasture Damage > Pest > Pest AlertIn grass grub prone areas 2 and 3-year-old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer the most protection and maximise returns from the cost of intervention.
Social tagging: AgPest > Grass > Grass grub > Pasture > Pasture Damage > Pest AlertIf clover root weevil is an issue in your area, pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover-free break crop provides a temporary weevil-free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Social tagging: Clover > Clover root weevil > Pasture > Pasture Damage > Pest > Pest AlertClover root weevil will be very obvious in most areas. While chemical control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed
Social tagging: Clover > Clover root weevil > Nitrogen > Pasture > Pasture Damage > Pest AlertWatch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Social tagging: Grass grub > Pasture Damage > Pest Alert > Tasmanian grass grub beetleMowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Social tagging: Californian thistle > Weed > Weed AlertWhen ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: Argentine stem weevil > Black beetle > Endophyte > Grass > SeedIn the northern North Island, damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte-infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide.
Social tagging: Black beetle > Pasture > Pasture Damage > Pest > Pest AlertThe early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Social tagging: Pest > Pest Alert > PorinaArgentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection
Social tagging: Argentine stem weevil > Cereal > Endophyte > Maize > Pasture > Pasture Damage > Pest > Pest AlertVelvetleaf seed was introduced to NZ as a contaminant of some fodder beet seed and planted in many properties throughout NZ. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property.
Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Look for and note porina flights as these can indicate when to adopt control measures later if required.
Social tagging: Pest > Pest Alert > PorinaApply herbicides to yellow bristle grass before seed heads ripen. Avoid moving stock from infested to clean paddocks – seeds can survive in dung.
Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds survive in hay. In contrast, yellow bristle grass seeds do not survive in well-made silage and wrapped baleage.
Social tagging: Seed > Weed > Weed AlertClover root weevil will be very obvious in most areas. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over grazed.
Social tagging: Clover root weevil > Pasture Damage > Pest > Pest AlertChilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Social tagging: Chilean needle grass > Pest Weed > Weed > Weed AlertThe Cost Benefit Analysis tool for Regional Pest Management has been revised and you may notice some changes when using the tool. If you have any questions, please consult the User Guide, which can be downloaded from the top right-hand corner of the tool.
You can find the Cost Benefit Analysis tool here: http://www.agresearch.co.nz/cba/
Social tagging: AgPest > Cost Benefit Analysis > Pest Alert > Weed AlertKeep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Social tagging: AgPest > Pest AlertChilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found here on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Social tagging: Biosecurity > Chilean needle grass > Grass > Invasive > Pest Weed > Weed > Weed AlertLook for and note porina flights as these can indicate when to adopt control measures later if required. The most cost effective time for control is 8-12 weeks after the main flights which may occur in November, mid-January and/or late-February/early March (especially central North Island).
Social tagging: AgPest > Pest > Pest Alert > PorinaChilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Social tagging: AgPest > Chilean needle grass > Pest Weed > Weed > Weed AlertArgentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment. Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Social tagging: Argentine stem weevil > crops > Endophyte > Pasture > Pest AlertClover root weevil feeding will become obvious in November-January – U-shaped notches at the edge of clover leaves show adults are present. The presence of larvae may be indicated by the pasture appearing nitrogen deficient. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over-grazed. In the South Island this weevil will be appearing in some areas for the first time.
Social tagging: Clover > Clover root weevil > crops > Damage > Nitrogen > Pasture Damage > Pest AlertFor pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
Social tagging: Clover root weevil > Direct Drilling > Grass grub > Pasture Damage > Porina > SlugsIn Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining making the crop appear silver. Treat early if required to maximise effectiveness.
Social tagging: Clover > Clover flea > Damage > PestUse treated seed in black beetle prone areas to reduce adult numbers.
Social tagging: Black beetle > Pest Alert > SeedIf direct drilling new pastures or crops check for slugs as these can devastate establishing seedlings. An application of slug pellets may be required or control may be achieved by heavy stocking rates.
Social tagging: crops > Pasture > Pest Alert > Seedlings > SlugsWhen ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: Argentine stem weevil > Endophyte > Pasture
In established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
Social tagging: AgPest > Clover > Clover root weevil > Pest AlertField horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors machines are clean and ask where the machines have been.
This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
Social tagging: Weed > Weed AlertIf your run-out pasture was infested with summer-active grass weeds last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations allowing better subsequent establishment of young clover.
Social tagging: Clover root weevil > Pest Alert > Weed > Weed AlertIn Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Clover > Pest > Pest AlertIf clover root weevil is an issue in your area, pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover free break crop provides a temporary weevil-free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Social tagging: Clover root weevil > Pest > Pest AlertWhen ordering grass seed, select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2 , will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector at www.dairynzfvi.co.nz
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: Endophyte > PastureIf your run-out pasture was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
Social tagging: Weed > Weed AlertFor pastures badly affected by either grass grub or porina over winter needing renewal or new pastures, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation.
Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings.
Be aware that slugs and clover root weevil may also be present in damaging numbers.
Social tagging: Pest AlertPorina and grass grub damage is showing in lower North Island. The only option available to protect pasture now is insecticide
Damage to pastures often becomes very obvious in winter. Generally it is too late to prevent production losses which have already occurred but pastures may be saved and long term quality maintained if pests are controlled. If this is necessary, identify the pest and adopt appropriate control measures. Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
Check established pastures for broadleaved weeds and apply herbicide as necessary once clover growth has slowed.
In areas where Tasmanian grass grub can be a problem, damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching control may only be warranted if it is required to preserve pasture plants.
Social tagging: Pest AlertPorina damage especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu from caterpillars arising from late February/March flights may only now be becoming apparent. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.
Social tagging: Pest AlertGrass grub and porina damage will now be evident in most areas. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging. Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest. By now production losses have already occurred but treatment may save the affected pastures.
Make preparations for winter spraying of weeds if required. Scout paddocks and map infestations of weeds such as ragwort and thistles. Develop strategies for ongoing management of weedy areas, e.g. grazing, set-aside, spraying, nutrient or lime applications etc.
Grass grub and porina damage will now be evident in most areas. By now production losses have already occurred but treatment may save the affected pastures. Conventional insecticide is the only control option likely to give control of grass grub in all areas and of porina in the South Island. North Island porina are still susceptible to diflubenzuron until mid-July. Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that plants are lost from pastures.05
Check new pastures and apply herbicide as necessary to control broadleaved weeds (6-8 weeks after establishment).
Social tagging: Pest AlertTasmanian grass grub damage may be showing. Check pastures to determine if control is warranted.
Social tagging: Pest AlertIn the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Give thought to sowing resistant plants for future pastures. See DairyNZ Pasture Renewal Guide
Social tagging: Pest AlertCheck new pastures and apply herbicide as necessary to control broadleaved weeds (6-8 weeks after establishment).
Social tagging: Pest AlertGrass grub or porina damage may be showing. Grass grub damage is indicated initially by loss of clover, patches of pasture turning yellow and becoming soft under foot. Porina damage appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Heavy rolling, high stocking rates or N application may provide some relief from grass grub but insecticide (diazinon) may be the only recourse. It is too late to control porina using diflubenzuron in most southern areas, conventional insecticide is still effective. Caterpillars from late February/March flights in the North Island and the South Island West Coast are still susceptible to diflubenzuron.
Social tagging: Pest AlertIf velvetleaf seeded in your fodder beet last year, it might be seen this year as a patch 2-3m in diameter. Continue surveillance for this weed and report anything suspicious to MPI on 0800 80 99 66.
For more information go to https://www.mpi.govt.nz/protection-and-response/responding/alerts/velvetleaf/
Social tagging: Pest AlertIn areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted.
Social tagging: Pest AlertIn Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness. See NZNovachem Agrichemical Manual
Social tagging: Pest AlertIn the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Social tagging: Pest AlertIn areas where grass grub or porina are a concern inspect pastures now for early damage. Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow and later becoming soft under foot. Porina damage initially appears as small (approx 5 cm dia.) areas of bare ground. Both pests should be controlled as early as possible to maximise returns and protect long term pasture production and quality. Although heavy rolling, high stocking rates and application of nitrogen can lessen damage, conventional insecticide (diazinon) may be the only recourse. It is now generally too late to obtain good control of porina using diflubenzuron, although in much of the North Island caterpillars from February/March flights are still susceptible. In most cases porina control now needs to be by conventional insecticide.
Social tagging: Pest AlertIf importing hay from other farms / regions be aware of unwanted weeds – many weed seeds can survive in and be spread via hay. Record the areas where hay has been fed out and regularly check these areas for new weeds after autumn and late spring rains- get rid of unwanted weeds before they become established. If you don’t recognise a weed get it identified.
Social tagging: Pest AlertPlantain moth numbers are building up and may increase dramatically after rain if warm conditions continue. Check with agchem reps. for insecticide options.
Social tagging: Pest AlertDue to dry weather the pastures are very open. There may be a flush of weeds after the first rain- treat if severe. Pennyroyal can also become dominant after a drought and would need to be treated with 2,4-D early in spring if a problem.
Social tagging: Pest AlertIn areas where Tasmanian grass grub can be a problem damage may be seen. Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Large numbers have been observed in southern Waikato.
Social tagging: Pest AlertNorthern North Island watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Pest AlertIn grass grub prone areas 2 and 3 year old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Social tagging: Pest AlertLate flights of porina may occur in the North Island, especially in Hawkes Bay, Taranaki, Wairarapa and Manawatu. These could result in damage appearing in June in infested paddocks. Look to apply diflubenzuron in late April-mid May.
Social tagging: Pest AlertWhen ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass AR1,AR37 and diploids with NEA2 will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector on www.dairynzfvi.co.nz. Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: Pest AlertMowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Social tagging: Pest AlertIf pasture establishment by direct drilling is going to be used check those pastures for slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants. Wet sacks can be laid in the paddock, slugs will shelter under these and be seen on the pasture surface if inspected after 2-3 days – more than 2 slugs per sack could result in seedling loss. To detect grass grub dig at least 10 15 x15 cm holes 15 cm deep and search the soil – as few as 1 grub/hole could cause damage.
Social tagging: Pest Alert
In Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover and treat early if required to maximise effectiveness.
Social tagging: Pest AlertIn grass grub prone areas 2 and 3 year old pastures should be inspected to determine if potentially damaging levels are present. Early treatment will offer most protection and maximise returns from the cost of intervention.
Social tagging: Pest AlertIf clover root weevil is an issue in your area, pasture renewal should incorporate a non-clover break crop. This weevil cannot survive in the absence of clover so a clover free break crop provides a temporary weevil free environment that will allow clover seedlings to establish before the weevil reinvades. This will also reduce plant nematodes, plant pathogens and weeds and benefit the new pasture.
Social tagging: Pest AlertClover root weevil will be very obvious in most areas. While chemical control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed
Social tagging: Pest AlertWatch for Tasmanian grass grub beetle flights. Beetles are attracted to lights at night. Large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Social tagging: Pest AlertMowing Californian thistle during rainfall can improve control of this weed by 30% as compared to mowing during dry weather. Best time to do this “wet mowing” is in February/March when the fungi thought to be responsible for this effect are producing spores on the thistle. The effect is likely to be greatest if some members of the thistle population to be mowed are showing signs of disease (wilting, yellowing, dieback).
Social tagging: Pest AlertDue to cooler nights and generally colder conditions than normal in many areas, velvetleaf has been slow to emerge. Therefore, surveillance in fodder beet crops for this nasty weed should be extended from now through to March.
Social tagging: Pest AlertWhen ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
Social tagging: Pest AlertThe early flight of porina moths has passed but the second flight significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight mid January to mid February is the optimal time to be applying diflubenzuron.
Social tagging: Pest AlertIn the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by AR37, Endo5 and NEA2 endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Social tagging: Pest AlertArgentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, at this time of year. This also applies to cereal and maize crops. If it is possible, delay sowing until early March when much of this threat will have passed. See DairyNZ Pasture Renewal Guide for endophyte selection
Social tagging: Pest AlertLast year velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with. For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Pest AlertClover root weevil will be very obvious in most areas. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be overgrazed.
Social tagging: Pest AlertArgentine stem weevils increase in significance over summer. Be aware that seedling grasses, even those infected with endophyte, are very susceptible to damage from this pest if numbers are high. This also applies to cereal and maize crops. Coated seed or pre-emergence insecticide application can prevent damage.
Social tagging: Pest AlertThe early flight of porina moths has passed but the second significant flight is about to occur in the South Island and could take place anytime between now and the end of February. Further flights may occur in March in the North Island. In areas that experienced an early (October/November) porina flight, mid-January to mid-February is the optimal time to be applying diflubenzuron.
Social tagging: Pest AlertWatch for Tasmanian grass grub beetle flights, large numbers of beetles flying may indicate potential damage from the larvae in autumn and winter.
Social tagging: Pest AlertIn the northern North Island damage from black beetle larvae may be showing. Unfortunately little can be done to prevent this. Adults are deterred by some endophyte- infected grasses which will reduce egg laying and larval numbers. See DairyNZ Pasture Renewal Guide
Social tagging: Pest AlertKeep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
Social tagging: Pest AlertLast year velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ.
To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated, but there could be others that have not been picked up. Similarly there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property.
Velvetleaf is declared an Unwanted Organism by MPI and occurrences must be reported and dealt with.
For further information phone the MPI hotline 0800 80 99 66 or go to MPI website, or go to AgPest, or contact your regional council.
Social tagging: Pest AlertLook for and note porina flights as these can indicate when to adopt control measures later if required.
For further information on porina, including identification, impacts and control methods please click here.
Social tagging: Pest AlertApply herbicides to yellow bristle grass before seed heads ripen.
Avoid moving stock from infested to clean paddocks – seeds can survive in dung. Don’t make hay from paddocks heavily infested with yellow bristle grass or other summer growing grass weeds – the seeds can survive in hay. In contrast, yellow bristle grass seeds are highly unlikely to survive in well made silage and wrapped baleage.
For further information on yellow bristle grass, including identification, impacts on your pasture and control methods please click here.
Social tagging: Pest AlertClover root weevil will be very obvious in most areas.
While control is generally not an option, careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over grazed.
For further information on clover root weevil, including identification, impact on your pastures and control methods click on the links below:
Social tagging: Pest AlertChilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge.
Each seed has a 7cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay.
If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
Click here to learn more about Chilean needle grass.
Social tagging: Pest AlertPlantain moths and caterpillars are beginning to build up. Monitor stands closely, particularly pure and plantain/clover stands, for the presence of moths or caterpillars.
Treat early to prevent large infestations and to minimise damage.
For further information on this pest, including identification, impact on your pastures and control methods click on the link below:
Social tagging: Pest AlertKeep an eye on aphids, diamondback moth caterpillars and white butterfly caterpillars in brassica crops. With warm summer temperatures, and following the mild winter in the South, these can increase quickly. Treating these pests before high numbers occur will provide greatest economic return.
For further information, including identification, impact and control on any of these pests please click on the links below:
Social tagging: Pest AlertChilean needle grass will become evident in pastures during November and December as its distinctive purple-coloured spikelets, with their developing long-awned needle-sharp seeds, emerge from elongating flower stems. Details of this invasive grass can be found on AgPest. This grass is most likely to be found in pastures on north/west-facing drought-prone slopes. If you suspect that you have it, please contact your local council biosecurity people for identification and management advice.
Social tagging: Chilean needle grass > Damage > Pest AlertLast year velvetleaf seed was introduced to NZ as a contaminant of fodder beet seed and planted in many properties throughout NZ. To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated but there could be others that were not picked up. Similarly there may be paddocks where velvetleaf was present but not found.
Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property. Velvet leaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with.
For more information phone the MPI hotline 0800 80 99 66 or go to MPI or go to AgPest, or contact your regional council.
Social tagging: Damage > Pest Alert > VelvetleafLook for and note porina flights as these can indicate when to adopt control measures later if required.
For further information on Porina including biology, impact and control, follow the link below:
Social tagging: Damage > Pest Alert > PorinaChilean needle grass will become evident in pastures in November-December. Keep an eye out for the reddish purple colour of the seed heads when they first emerge. Each seed has a 7 cm long awn (bristle-like tail). This grass is most likely to be found in pastures on north/west-facing drought-prone slopes but may be present in contaminated stock feed / hay.
If you suspect that you have it, please contact your local council biosecurity people for identification and management advice immediately.
For further information on Chilean needle grass including biology, impact and control, follow the link below:
Social tagging: AgPest > Chilean needle grass > Pest AlertArgentine stem weevil is building up in the North Island and will need to be considered in pasture and crop establishment.
Insecticide coated seed may be a viable control option and insecticide application can provide temporary relief from this pest and allow seedlings to establish. Argentine stem weevil is a significant threat to seedling grasses, even those infected with endophyte, cereals and maize crops. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
For further information on Argentine stem weevil including biology, impact and control, follow the links below:
Social tagging: Argentine stem weevil > Damage > Pasture > Pest Alert
Clover root weevil will be very obvious in most areas –U shaped notches at the edge of clover leaves show adults are present. The presence of larvae may be indicated by the pasture appearing nitrogen deficient. While control is generally not an option careful management of clover will help maintain pasture quality. Additional nitrogen may need to be applied to pastures and clover should not be over grazed.
For further information on clover root weevil including biology, impact and control, follow the links below:
Social tagging: Clover root weevil > Pasture > Pest > Pest AlertAt the end of the month look for porina flights – indicated by large numbers being attracted to lights at night, as these can indicate when to adopt control measures at a later date if required.
For further information on porina including identification, biology, control and management click here.
Social tagging: Pest AlertLast year velvetleaf seed was introduced to New Zealand as a contaminant of fodder beet seed and planted in many properties throughout New Zealand..
To date more than 250 properties have been found to be infested with this terrible weed. Six different lines of fodder beet seed have been identified as contaminated, but there could be others that were not picked up. Similarly there may be paddocks where velvetleaf was present but not found. Therefore, if you have either grown fodder beet or received fodder beet onto your property you need to be vigilant and keep an eye out for this weed and do not let it establish on your property.
Velvetleaf is declared Unwanted Organism by MPI and occurrences must be reported and dealt with.
For more information phone the MPI hotline 0800 80 99 66 or go to MPI website , or go to AgPest, or contact your regional council.
Social tagging: MPI > Pest AlertLook for brassica springtails before sowing brassica crops. Place a white card or cloth on the soil surface and gently disturb the soil around it. This will cause the springtails to jump and land on it making them easier to see.
For further information on brassica springtail, including identification, biology, impact and control click here.
Social tagging: brassica > crops > Pest AlertFor pastures badly affected by either grass grub or porina over winter and needing renewal, consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the south, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers.
For further information on either of these pests, including identification, biology, impact and control, click on the links below:
Social tagging: Direct Drilling > Pasture > Pest AlertUse treated seed in black beetle prone areas to reduce adult numbers.
For further information on black beetle including identification, biology, impact and control click here.
Social tagging: Pest AlertIf direct drilling new pastures or crops check for slugs as these can devastate establishing seedlings. An application of slug pellets may be required or control may be achieved by heavy stocking rates.
For further information on field slug identification, biology, impact and management click here.
Social tagging: Damage > Direct Drilling > Pest Alert > SeedlingsWhen ordering grass seed select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order. In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against Porina.
See DairyNZ Pasture Renewal Guide for a guide to endophyte selection.
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
For further information on weed and pest identification, biology, impact and management click here.
Social tagging: Pest AlertIn established pastures with high levels of clover root weevil, the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
For further information on clover root weevil, including identification, biology, impact and control click here.
Social tagging: Damage > Nitrogen > Pest AlertIn Northland, South Auckland, Waikato and the Bay of Plenty watch for clover flea damage to clover – this appears initially as small holes in leaves, more severe damage results in only leaf veins and the lower leaf surface remaining making the crop appear silver. Treat early if required to maximise effectiveness.
For further information on clover flea, including identification, biology, impact and control click here.
Social tagging: Pest AlertField horsetail (Equisetum arvense) is a very difficult to control perennial weed that regrows each spring/summer from an extensive underground root system. Preventing establishment is the best form of control. Make sure your contractors machines are clean and ask where the machines have been. This root system comprises actively growing rhizomes that can penetrate to more than 1 m in depth, from which green fern-like fronds grow each year. Attached to the deeper rhizomes are small tubers which remain dormant while the rhizome stays alive. Upon the death/decay of the rhizome, or when it becomes detached due to cultivation or other means, the tubers are able to produce new plants.
For further information on Field horsetail including identification, biology, impact and management click here.
Social tagging: Invasive > Pest AlertIf your run-out pasture was infested with summer-active grass weeds last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures. Forage crops will also disrupt clover root weevil populations, allowing better subsequent establishment of young clover.
For further information on weed and pest identification, biology, impact and management visit our AgPest Online Pest Directory.
Social tagging: Damage > Pasture > Pest AlertIn established pastures with high levels of clover root weevil the clover may be adding little in the way of nitrogen to the pasture and compensatory nitrogen applications may be required.
For further information on clover root weevil including biology, impact and control, follow the links below:
Social tagging: Clover > Damage > Nitrogen > Pasture > Pest AlertIf clover root weevil is an issue in your area, pasture renewal should incorporate a non-clover break crop.
This weevil cannot survive in the absence of clover, so a clover free break crop provides a temporary weevil free environment that will allow clover seedlings to establish before the weevil reinvades. This will also produce plant nematodes, plant pathogens and weeds, and benefit the new pasture.
For more information on Clover root weevil, including biology, impact and control, click on the link below:
Social tagging: Clover > Damage > Pasture > Pest AlertWhen ordering grass seed, select suitable endophytes and check that the endophyte you select has been assessed in the grass variety you order.
In ryegrass, AR1 and AR37, and diploids with NEA2, will protect against Argentine stem weevil, AR37, Endo5 and NEA2 against black beetle and AR37 against porina. See DairyNZ Pasture Renewal Guide for a guide to endophyte selection or the cultivar selector at www.dairynzfvi.co.nz
Endophyte levels in the seed should be at least 70% and have been assessed in the last 3 months.
For further information on identifying and controlling pasture pests, visit our website:
Social tagging: Damage > Endophyte > Pasture > Pest AlertIn Northland, South Auckland, Waikato and the Bay of Plenty, watch for clover flea damage to clover and treat early if required to maximise effectiveness.
For further information on this pest, including biology, impact and control, click on the link below:
Social tagging: Clover > Damage > Pasture > Pest AlertIf your run-out pasture was infested with summer-active grass weeds (such as yellow bristle grass) last summer, consider growing a forage crop for one or two summers prior to sowing the perennial pasture. This provides the opportunity to selectively spray the summer-active grasses and prevent weed seeds from replenishing the seed bank and infesting newly sown pastures.
For further information on pasture weed pests, including biology, impact and control, please follow the links below:
Social tagging: Damage > Pasture > Pest AlertIf pasture establishment by direct drilling is going to be used, check those pastures for pests; especially slugs and grass grub as even low numbers can devastate young seedlings of pasture or crop plants.
Fur further information on these pasture pests, including biology, impact and control please click on the links below:
Social tagging: Damage > Direct Drilling > Pasture > Pest Alert > SeedlingsFor pastures badly affected by either grass grub or porina over winter and needing renewal consider direct drilling. This will preserve naturally occurring diseases of these pests that are building up in the soil and which will provide long term population regulation. Leave sowing as late as possible as both pests, especially in the South, may still be feeding and could devastate establishing seedlings. Be aware that slugs and clover root weevil may also be present in damaging numbers. Use of treated seed is recommended.
For further information on these pasture pests, including biology, control and management please follow the links below:
Social tagging: AgPest > Damage > Pasture > Pest AlertWater Pepper has been added to the AgPest online Pest Directory.
It is a Very common weed found in damp pastures and near waterways throughout lower areas of both North and South Islands. It is rarely grazed and therefore replaces more useful pasture species in damper areas within pastures.
For further info on Water pepper, including identification, biology, impact & control click here: https://live-agpest.pantheonsite.io/?pesttypes=water-pepper
Social tagging: Pest AlertHairy buttercup has been added to the AgPest online Pest Directory.
Hairy buttercup is not considered poisonous to livestock but because dairy cows tend to avoid it and prefer to graze grasses and clovers, it can become dominant in the pasture.
More info, including identification, biology, impact and control here: https://live-agpest.pantheonsite.io/?pesttypes=hairy-buttercup
Social tagging: AgPest > Pest Alert > Weed AlertRecently we have added 7 new weed pests to the AgPest Directory.
The new profiles on AgPest have information relating to the identification, biology, impact and control for the following weeds:
AgPest contains a number of New Zealand pasture weeds and pests, which have been chosen in consultation with key farming, industry and research personnel. We will continue to identify and add more weeds and pests to the directory.
Click here to view our Pest Directory
Found something new on your farm? Not sure if it’s a pest or not? Click here to use our free online identify tool
Social tagging: Pest directoryDamage to pastures often becomes very obvious in winter. Generally it is too late to prevent production losses which have already occurred, however pastures may be saved and long term quality maintained if pests are controlled.
If this is necessary, identify the pest and adopt appropriate control measures.
Bear in mind that spring growth is not far away and may outgrow the effect of the pest.
To identify a pest on your farm, and to view control and management options click here.
Social tagging: AgPest > Pasture Damage > Pest AlertPorina and Grass Grub damage is showing in areas of the lower North Island.
The only option available to protect pasture now is insecticide.
For further information on these pasture pests follow the links below:
Social tagging: AgPest > Pasture Damage > Pest AlertCheck established pastures for broadleaved weeds and apply herbicide as necessary once clover growth has slowed.
Need to identify a weed or pasture pest on your farm? Head on over to our website www.agpest.co.nz where you can use our free online identify tool and learn more about the impacts, biology and information on how to manage pasture pests and weeds.
Social tagging: AgPest > Damage > Pasture > Pest AlertDamage may be showing in areas where Tasmanian grass grub can be a problem.
Check pastures particularly around stock camps and assess numbers to determine if insecticidal control is warranted. Bear in mind feeding is slowing and with spring growth approaching, control may only be warranted if it is required to preserve pasture plants.
For further information on Tasmanian grass grub, including biology, impacts and control please follow the link below:
Social tagging: AgPest > Damage > Pasture > Pest AlertPorina damage especially in Hawkes Bay, Taranaki, Wairarapa, Ruhapehu, Taupo districts and Manawatu, from caterpillars arising from late February/March flights may only now becoming apparent.
Careful consideration needs to be given to control options as spring growth may occur before damage becomes such that the plants are lost from pastures.
For further information on Porina, including biology, impact and control, please follow the link below:
Social tagging: AgPest > Damage > Pasture > Pest AlertGrass grub and porina damage will now be evident in most areas.
Grass grub damage is indicated initially by loss of clover and subsequently by patches of pasture turning yellow. At this time of year these patches become soft under foot and are prone to pugging.
Porina damage will show as bare areas of pasture often with only weed plant species present. Conventional insecticide is the only control option likely to give control of either pest.
By now production losses have already occurred but treatment may save the affected pastures.
For further information on either of these pests please follow the links below:
Social tagging: AgPest > Damage > Pasture > Pest Alert
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