Latest weapon in couch battle
Latest weapon in couch battle
THE first herbicide specifically for controlling couch in growing winter wheat should be available to treat about 50,000ha (124,000 acres) next spring.
Bayers Attribut (propoxycarbazone-sodium) has just received PSD approval, giving growers an alternative to pre-harvest Roundup (glyphosate), the firm believes.
In trials, a full rate of the residual spring-applied product has averaged over 90% couch control, says Peter Stacey. "It will be very attractively priced."
Its clear advantage over pre-harvest glyphosate is that it reduces competition from couch and other grasses earlier in the season, he says. And another competitor – Monitor (sulfosulfuron) – which has some couch activity, has given only 82-83% couch control in Bayer trials.
Although Attributs only label target is couch, it works against blackgrass and has given 70-80% control of sterile brome and higher levels in meadow, rye and soft bromes, says Mr Stacey. It also suppresses onion couch, wild oats, loose silky bent and canary grass.
"We think it will be especially useful in blackgrass control programmes for cleaning up small amounts left in the spring."
For couch and brome, split treatment gives better results than a single application, for which the latest timing is flag leaf just visible (GS37), he says.
Attributs only following-crop restriction is that no oilseed rape may be sown the same year. *
IN-CEREALCOUCHKILLER
• Alternative to pre-harvest glyphosate.
• Removes weed competition sooner.
• Useful on blackgrass & other grasses.
• Currently for winter wheat only.