Black-grass control begins with understanding first principles and then tailoring a plan depending on the level of infestation. CPM finds out more.
Few problems generate as much discussion as black-grass and farmers are always looking out for new methods to control it. However, with so many different ideas out there, how do farmers work out what’s required on their farm?
James Boswell, of distributor Hutchinsons, says that control of this competitive weed used to come out of a chemical can, but with the increased intensity plus widespread resistance to a range of active ingredients, growers must move to cultural control methods for black-grass as their first port of call.
James says that he would normally sit down with his customers and carry out a review of black-grass across the farm. "It used to be a weed of heavy soils and winter rotations, but it is now found across most arable land. We need to get an idea of how intense the infestation is, what has worked in the past and what hasn't. Firstly, I would advise growers to introduce a spring crop, either maize or spring barley. This has a positive effect on reducing the black-grass population, as the majority of black-grass germinates around the 15th October.
Carefully targeting cultivations and selecting more competitive varieties will help wheat growers maximise cultural black-grass control this autumn.
Trials at the Hutchinsons Mollington Regional Black-grass Centre, at CA & A Hall & Son's farm near Banbury, Oxfordshire, first reported in A&AF in June, are now showing there can be significant benefits to weed control from using well-timed, shallow cultivations and growing more competitive varieties.
But as fields begin to be cleared this harvest, Hutchinsons Technical Manager Dick Neale urges growers to be patient with cultivations to maximise their benefits.
New trials in Oxfordshire are showing how crop competition can make a valuable contribution to black-grass control within an integrated strategy.
It is the fourth year of the Hutchinsons trials at the Mollington black-grass centre near Banbury, where weed populations have fallen from 1,500 plants/sqm to 50 plants/sqm, by focusing on cultivations, soil health and rotation.
The dramatic reduction in black-grass pressure has allowed winter wheat to be reintroduced to the site for the first time in four years and Hutchinsons agronomist Toby Kellie is investigating how wheat can be managed to suppress black-grass, through drill choice, variety and seed rate.