Bayer: Spraying herbicide very soon after drilling crucial for weed control

Bayer CropScience is reminding growers about the value of keeping the gap between drilling and pre-emergence herbicide application small. Weed control with herbicides offers up to 80 percent control of black-grass, and the period around drilling is vital for  weed control.

“In trials, we aim to apply Liberator within two days of drilling, which is a true pre-emergence timing and compare this to applications at later dates,” Darren Adkins of Bayer CropScience said. “We see a significant dip in performance at those later dates. If grass weeds are an issue, only drilling when there is time and the right conditions to spray is essential. A gap of more than a few days can give weeds the chance to get established and are then consequently tougher to kill.”

Liberator is a pre-emergence herbicide composed of flufenacet and diflufenican; the flufenacet goes under the soil approximately five centimeters while diflufenican remains on the surface of the soil. The flufenacet kills the weeds before they break through the soil, and the diflufenican kills weeds that already have broken through the soil.

“Only spraying when there is soil moisture or rain is forecast is a must because without it, flufenacet cannot move within the soil profile,” Adkins said. “In previous years, there have been problems when people drill in very dry conditions.”

Adkins also advises farmers to delay drilling until mid-September to mid-October, which will usually provide more moisture in the soil. However, Adkins acknowledges that waiting to drill this late in the season is not without risks. “If you are adamant about keeping the gap short, then it is possible that there won’t be the opportunity to drill all the land in autumn. If this is the case, then growers need to be prepared to use a contractor to apply or consider a spring crop instead.”