Tackle cleavers early

Early cleaver control is vital this season in order to minimise the risk of yield losses up to 20%, according to experts.

In wheat and barley, the best time to treat them is around growth stage 30, said Association of Independent Crop Consultants chairman, Patrick Stephenson.

“Recent rain means crops are still coming on well and we’re expecting the early-drilled crops to have reached that stage during early March.

“Traditionally, cleaver control has tended to be a job for April or May, but as with all weeds, the earlier they’re treated the better.”

Dow AgroSciences’ James Knight agreed, highlighting results from a recent survey which found that cereal growers and advisors are treating cleavers up to six weeks earlier than five years ago.

“April is now recognised as the best time to control cleavers in cereals for maximum yield benefit. Cleavers start to reduce yields as early as GS 29-32.”

Better understanding of the weed’s biology and development of herbicides, such as Starane XL (fluroxypyr + florasulam), with a wider window of application and wider weed spectrum have contributed to this earlier control, he noted.

Cleavers start germinating in the autumn and continue to emerge throughout the winter, so growers have plenty of opportunity to control them, added Bayer CropScience’s Peter Stacey.

He suggests using Eagle (amidosulfuron), which can be applied from 1 February until GS 49.

“With increasing responsibilities towards anti-resistance stewardship and environmental management, it’s also useful to remember that Eagle is one of the few sulfonylurea herbicides that Bayer recommends in sequence with Atlantis (iodosulfuron + mesosulfuron).”

To keep track of the latest crop developments, direct from agronomists around the country, see FWi’s Crop Watch – updated every Tuesday.