UK: Treat blackgrass flexibly, says Dow

Blackgrass - a threat to wheat crops

Blackgrass - a threat to wheat crops - Credit: submitted

Cereal farmers battling blackgrass this autumn should be flexible in the programmes they adopt, farm chemicals maker Dow AgroSciences says. After last year’s difficult season, the blackgrass challenge is high, herbicide expert Stuart Jackson warned. “The indications are that blackgrass dormancy is low, so with harvest out of the way the first vital step is to use a stale seedbed to burn off early emerging grass weeds.” Once the crop is drilled, applying a pre-emergence is the next essential step.

“An incorrect decision here, can impair the rest of the programme,” warns Mr Jackson. “We urge growers to avoid ALS products at this stage. It is far better to use products, such as pendimethalin, tri-allate or prosulfocarb as the partner to flufenacet for this early season control of emerging weeds and keep the options open to use ALS products, such as UNITE (pyroxsulam+ flupyrsulfuron-methyl-sodium) once crops and weeds emerge in the autumn.”

After last year’s difficult autumn, few growers will be prepared to delay drilling. However, Mr Jackson urges growers to leave the heaviest infested fields to the end of the autumn drilling campaign to optimise stale seedbed control.

“In the very worst infestations, there is a case for reviewing the cropping programme to optimise the benefits of rotation and cultivation in fighting blackgrass,” he said.

“To help farmers take a more holistic view Dow AgroSciences has created the LifeCycle website - where experiences, from farms and researchers, can be shared on how key arable weeds can be controlled across the whole farm rotation.”