Cleavers pose bigger threat to yields this season

UK - April 06, 2009

East Anglian agronomist Malcolm Perry reports that cleavers look set to be more of a headache than usual in winter wheat this spring, despite autumn treatments.

Mr Perry, an Agrovista agronomist, says: “Unlike other parts of the country we were able to apply a lot of the residual pendamethalin + flufenacet last autumn to control a wide range of weeds.

“They have worked particularly well against blackgrass, the main target in our area. However, I reckon a quarter to a third more fields than usual will need a specific cleavers treatment this spring. At present, I’m recommending Boxer but when the weather warms up I will move on to Starane XL or Starane Vantage.”

Dow AgroSciences technical expert Stuart Jackson warns: “Growers need to act sooner rather than later to protect crops from the yield robbing effects of cleavers which are seven times more competitive than blackgrass. They pose the biggest threat to cereal profits so herbicide choice is critical for maximum returns.”

Most yield loss occurs when cleavers’ control is delayed until after GS32. For early treatment Boxer (florasulam) is ideal. It is effective in cold, slow growing conditions, when speed of control is not so important. Boxer also controls other weeds including mayweeds, chickweed, volunteer oilseed rape and other brassica weeds and is compatible with a range of tank mixes.

“Once the weeds start growing quickly in warm weather Starane XL or Starane Vantage (florasulam and fluroxypyr) become the product of choice,” adds Mr Jackson.

“These products give a quick knockdown of cleavers, as well as controlling chickweed, brassica weeds and mayweeds. They offer excellent flexibility with one of the broadest application windows as well as flexible application rates to suit weather and weed growth.”