Using seasonal advantage to control black-grass


This year’s exceptional conditions present an opportunity to continue to tackle persistent black-grass. At one of the BASF Ask the Expert meetings, Dr Sarah Cook, senior research consultant at ADAS, spoke to a group of farmers near Chipping Norton to give some advice on making the most of this seasons weather patterns.

The importance of black-grass control is clear to every arable farmer, but how to achieve that goal is more elusive. Populations may be reduced one year but return the next.

“Our testing shows that black-grass dormancy is low this year and along with the very dry conditions could present an opportunity to control the weed,” says Sarah Cook.

“Leaving soil uncultivated will mean that some of the black-grass will be predated, while other seeds will germinate. Cultivating as shallow as possible will keep black-grass seeds in the top 5cm of soil where they can germinate and minimise the risk of bringing up old seed from previous years.

“Spray off the germinated black-grass seed with the appropriate dose of glyphosate before drilling. It is tempting to start drilling earlier than normal because of the dry weather in the hope of not being caught out by the arrival of rain but resist that temptation – even very heavy rain is only likely to water the soil and not water-log it. Between 24 and 48 hours after drilling apply a robust pre-emergence herbicide, which combined with all the other actions should give you the best chances of control.”

Dr Cook says that farmers should take a field-by-field approach to controlling black-grass and try and minimise the risk of weed seeds transferring from farm to farm by vehicles and other means.