Investigating alternative residual herbicides for annual weed control in raspberry
Abstract: Efficient and cost effective weed control is important in raspberries; A three year project, funded by the Horticultural Development Company was designed to test a range of new residual herbicides, for weed control efficacy and crop safety in raspberry. In year one nine actives were tested for their crop safety and weedcontrol efficacy and in years two and three the most promising herbicides were taken forward as tank mixes in combination with industry standard herbicides to enhance the spectrum of weeds controlled and to further assess crop safety. Flazasulfuron stood out as the most effective herbicide, and when used in combination with pendimethalin the weed control was comprehensive and more persistent than any of the other treatments. Tank mixes with pendimethalin + dimethenamid-p, clomazone and flufenacet + metribuzin were less persistent but are worth developing for raspberries if extensions of approval can be obtained. No effects on yield were recorded and no residues were detected above MRLs.