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 Alert