Post-emergence control for weed competition in peas
Continued dry weather conditions will compromise the efficacy of pre-emergence herbicides in peas this season, where the emerging crop is especially susceptible to weed competition for moisture and available nutrients.
Syngenta Specialist Crops Manager, Bruce McKenzie, highlights that the herbicide, Skirmish, has the added flexibility of pre and post-emergence application in peas, right through to the second node stage of the crop. "It gives growers and agronomists the chance to see the weed spectrum emerging in the field, and to treat accordingly," he advises.
The PGRO advocate that, where broad-leaved weeds e.g. polygnums, mayweed or volunteer oilseed rape are present, a tank-mix of Skirmish with a reduced rate of bentazone will give added contact activity, along with residual weed control whilst the crop establishes. "Dry soil conditions will slow crop establishment, so avoiding any further check from weed competition will be even more important this season," warns Mr McKenzie. "When applying any post-emergence application growers should ensure leaves have sufficient wax layer before application."
He reports that peas have, for the most part, been drilled into good seedbed conditions this season. But he advises that where dry conditions have left clods, the use of angled spray nozzles will provide a significant benefit in achieving good soil coverage with Skirmish, to enhance residual weed control.
"Syngenta trials have shown that when spraying with conventional nozzles, clods cast a ’shadow’ to a distance of about 75% of their diameter that receives little or no spray," he advises. "Fitting angled Syngenta Defy Nozzles and alternating the spray pattern forwards and backwards along the spray boom effectively coats all around the soil clods and across the surface to give the best possible herbicide performance."
