Bayer weed control specialist, Tom Scanlon points to surprisingly high levels of black-grass infestation seen in many very late-drilled crops this summer where the weather got in the way of seedbed quality and/or peri and post-em spraying.
At the same time, he urges everyone to be particularly conscious of the serious grassweed legacy from poor and patchy spring crops established in a bone dry April on soils damaged by the wet winter; not to mention OSR that has struggled to shake-off the challenge of cabbage stem flea beetle larvae.
“It is imperative we bear down hard on grassweeds in the best annual control opportunity we have if we are to prevent them taking advantage of the major holes this past season has opened-up in our defences,” he stresses.
“We know to our cost how little it takes for the likes of black-grass, brome and ryegrass to bounce back from several years of apparently good control, and the problems this can cause us for many years to come when they do.
“That’s why it’s so worrying to see how many growers involved in the latest in our series of Roundup national grassweed management studies are looking to sow winter wheat before mid-October this year.
Alongside rotational ploughing, spring cropping and stale seedbeds, delayed drilling continues to stand out as one of the most widely-valued cultural grassweed control techniques in the 2020 study, run with almost 200 growers across the country by Briefing Media.
Despite this almost half the study growers are currently looking to sow winter wheat on high weed risk fields before mid-October this season, with more than one in 10 planning to do so in September. What’s more, this rises to 80% and 26% respectively on medium weed risk fields.
