Growers are being reminded of best practice when applying Avadex (tri-allate) granules with a drill this autumn, to get the best grassweed kill.

The benefit of applying tri-allate with a drill-mounted applicator is that farmers are guaranteed a robust start to their herbicide programme if the weather changes and compromises occur following pre-emergence applications, says Hank King, Gowan country manager.

Additionally, it saves the cost of an additional pass to apply tri-allate separately.

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“Given the uncertain weather we have seen over the past few years at drilling time, it makes complete sense to take this approach where possible.”

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Hank says the most important requirement is that the product is applied according to the label and, being a pesticide, the drill operator must be PA4G qualified if the application is to be made in the same pass as the drilling operation.

“The granulator applicator also needs to be calibrated in its own right and include patternation testing. The aim is uniform coverage across the drill width for best efficacy,” explains Hank.

He advises operators to sow winter wheat below 40mm, as the crop seed can potentially germinate within the herbicide residual layer in the soil if it is sown shallower than this.

It is also essential that the drill slots are adequately closed and the seed covered when Avadex is spread at the back of the drill.

“Drills can often be run at a decent forward speed, but operators must remember that they need to drill at the speed of the slowest operation. In some cases, this means slowing down to ensure optimum product coverage.”

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He adds that it is the same for weather conditions. “Drilling can carry on in substantial winds without a problem, but this is not true for Avadex spreading,” Hank adds.

Rolling will consolidate the seed-bed, which aids crop establishment, reduces slug activity and provides better conditions for the efficacy of pre-emergence herbicides. However, seed depth must not compromised due to the rolling action.