Gowan is reminding growers and contractors that it offers free dummy Avadex granules for effective calibration.
Hank King, country manager, says that the dummy granules can be used up to three times before they need to be replaced, and can be requested through the Gowan website.
“These are the same granules that are used in the product, just without the active ingredient, and they closely reflect the product. Using dummy granules ensures the most accurate calibration.”
“Accurate calibration is important for product stewardship, which is complementary to efficacy. Grass weed control is a huge challenge, and we want to ensure growers get the most from the herbicides they use.”
Oxfordshire farmer and contractor, Will Hazell, says that he finds the Avadex application extremely accurate, using a Techneat applicator mounted on a 24m Sands sprayer.
“The Avadex (granule size) is so consistent out of the bag. Once you have it set right, it tends to run well for the whole season,” he explains.
He notes that the contracting acreage of Avadex application has reduced, but it isn’t because growers are not applying it.
“I wouldn’t say the usage of Avadex has gone down. With the grants available, a lot of people have bought new drills, and they tend to spend a little extra to have an Avadex applicator fitted to the back.
“I know some farmers who won’t even think about planting wheat without using Avadex.”
Best practice when using a drill
Hank notes that applying Avadex from a drill-mounted applicator guarantees a robust start to herbicide programmes, especially if the weather compromises any further pre-emergence applications.
“Given the uncertain weather we have seen over the last few years at drilling time, it makes complete sense to take this approach where possible.
“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.
When applying Avadex, he advises growers to sow winter wheat below 40mm to avoid germination within the herbicide residual layer. Growers also need to ensure that the drill slots are closed properly, covering the seed before Avadex is spread,
“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 Avadex coverage.
“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.”
Rolling can help to improve the efficacy of pre-emergence herbicides, as well as aiding germination and reducing slug activity, however, Hank warns that any rolling action should compromise the seeding depth of 40mm.