Ploughing in a reduced tillage system can reduce blackgrass incidence in winter wheat crops by an average of 69%, according to ADAS researcher Sarah Cook.

Ploughing is one of the most effective ways of tackling the invasive weed and resetting the system to bring the weed back down to a more manageable level.

The researcher also noted that ploughing once to reset the system will have little impact on the soil organic matter and is unlikely to affect it.

Spring cropping is another effective method of blackgrass reduction.

Planting a spring crop can reduce incidence by 88% as 80% of blackgrass germinates in the autumn, although there is now some spring blackgrass in the UK.

Leaving land fallow can reduce incidence by 70% to 80% by allowing the weed to germinate and be sprayed with glyphosate.

Other methods of reduction include delayed drilling in the autumn, which can reduce levels by an average of 31%.

Higher seed rates can reduce the incidence by 26% as the weed can be smothered out if the crop gets off to a good start.

Competitive cultivars work similarly, bringing about a reduction of 22%.

Levels of blackgrass reduction from cultural control methods in winter wheat, according to ADAS research

  • Ploughing: 69%.
  • Delayed drilling: 31%.
  • Higher seed rates: 26%
  • Competitive cultivars: 22%.
  • Spring cropping: 88%.
  • Fallowing – 70-80%.

    • Take-home messages from the conference

  • If you have a grass weed problem, talk to your adviser.
  • Take action straight away.
  • Get your grass weeds tested for resistance.
  • Implement cultural control methods.
  • Use pre-emergence herbicides, where possible.