Grass weeds were problematic in 2015, so take time to plan a strategy with your adviser to make best use of stubble cultivations.
Under cross-compliance, if you use glyphosate (Gallup, Roundup, etc.) between July 1 and December 1, then you must make sure you have green cover (weeds or crop) at inspection time.
However, if you grow ‘contract’ crops for seed/malting/milling, you can avail of a derogation to this rule.
Basically, you can apply glyphosate on 25% of your cereal land after October 15, with no requirement for green cover on this 25%.
Oilseed rape volunteers
Delay cultivations for two weeks after harvest of oilseed rape (OSR) when soils are moist (four weeks if dry).
OSR seed will germinate readily on top of the ground; burying it induces dormancy.
Annual grass weeds
Most annual grass weeds (for example, sterile brome, canary grass) will readily germinate after stubble cultivations, and can be successfully controlled with 540g/ha of glyphosate. However, weed seed germination may be delayed if conditions are very dry after cultivation.
Certain species of brome (meadow, rye and soft) need light to break dormancy, so are best left on the soil surface and not cultivated.
Perennial weeds (scutch, docks, creeping thistle, colt’s foot, corn mint and sow thistle, etc.) should be left uncultivated after harvest to produce new growth before spraying with glyphosate; watch compliance rules.
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