Control

Pasture establishment

• Any control strategy must reduce vulpia seed set and its seed bank to prevent new pastures becoming infested
• If vulpia is prevalent, vulpia plant litter should be incorporated into the soil before establishing a new pasture or sowing a crop to prevent allelopathic chemicals from leaching out of vulpia residues
• Residues release the most toxins 40 – 60 days after decomposition starts. Sowing crops/pastures after this period will minimise the impact of these toxins on the crop or new pasture
• Sowing one or more (successive) crops before establishing the pasture can allow the use of a selective grass herbicide to control vulpia.

Chemical control

• Application of simazine during winter will kill vulpia plants and its residual activity will prevent any fresh germination
• A mixture of simazine, dalapon and amitrole (often marketed as DAS) provides good control but also kills other grasses and many broad-leaf plants
• In one study comparing timing of application, best control was achieved by spraying with glyphosate when 70 – 80% of vulpia seed heads were visible
• A single application of a herbicide is unlikely to be effective – vulpia will rapidly re-invade from the seedbank if other measures (e.g. pasture renewal, grazing and repeat chemical application) are not used
• The Foundation for Arable Research (see references below) says ‘Consistent performers against hairgrass have been Nortron (2 l/ha effective in ryegrass seed crops when applied pre-emergence) and Gardoprim (teruthylazine). Other chemicals which have proved useful include Sencor, Teedal, Karmex, Kerb Flo and Avadex.’

Making hay or silage

• Cutting infested pasture for silage before vulpia seeds mature (e.g. in November) can reduce infestations
• Making hay (e.g. in December) can allow vulpia seeds to mature in the paddock before the hay is cut. Seeds may be dispersed in paddocks where the hay is fed out; making hay is not a good way to control vulpia.

Grazing management

• Grazing vulpia at strategic times can reduce infestations
• Heavy grazing in spring and autumn can reduce vulpia flowering, seed set and seed bank replenishment and also reduce seedling numbers
• The best time to graze vulpia in spring is when reproductive tillers begin to elongate and seed heads are visible; grazing at this stage helps to prevent further seed production before the plants die
• Sheep may avoid mature vulpia plants as they prefer other more palatable pasture species
• Note that autumn grazing alone can sometimes increase vulpia presence by increasing tillering
• Given the small window of opportunity for grazing, only a small area of a property can be targeted for grazing each year (e.g. paddocks in which pastures are to be established in the following autumn, the worst paddocks, etc)
• Fertiliser application and use of grass species and cultivars appropriate for the area can help desirable, pasture species to outcompete vulpia
• Rotational grazing proved better than continuous stocking for limiting the spread of vulpia in dryland pastures grazed by sheep in southern Australia (- see references under ‘Further Information’).