Concentrate on producing the best seed-bed possible for oilseed rape given the circumstances, and worry about herbicides after emergence, BASF’s Claire Tucker advises.
“The priority is drilling and seed-bed preparation. All the evidence points to good establishment as a pre-requisite of a successful oilseed rape crop.
“Focus on getting the best seed-bed you can and don’t be too concerned about getting herbicides on pre-emergence of the crop.
“One saving grace is that soils are moist and warm. Consequently crops are coming through very rapidly, which is good news,” she says.
But those crops are also vulnerable to weed competition and need treating with a post-emergence herbicide as soon as possible once crops have emerged, she points out.
Key oilseed rape herbicides, such as Novall (metazachlor + quinmerac), Springbok (dimethanamid-P + metazachlor) and Shadow (dimethanamid-P + quinmerac + metazachlor) can all be applied post-emergence once the crop reaches cotyledon stage, and control a broad-spectrum of weeds.
“But don’t delay any further – once the crop is at expanded cotyledon, early weeds, such as chickweed, shepherd’s purse and cranesbill will also be emerging. These must be targeted by cotyledon stage.”
Once past early post-emergence, weed control options become more limited and are more variable, she points out.