GROWERS have been told good soil health is key to retaining herbicides.

They should not be complacent when it comes to metazachlor and quinmerac usage this autumn and adopt good soil management practices to keep these important active ingredients on the market.

With the issue of metazachlor and quinmerac reaching raw surface waters and – at times – exceeding drinking water levels, Rob Gladwin, representative of the Metazachlor Matters stewardship initiative, stressed the importance of adopting Integrated Crop Managment (ICM) techniques, in order to retain access to metazachlor and quinmerac.

“Unfortunately, there’s no silver bullet when it comes to weed management, and significant weed problems won’t disappear overnight,” he said.

“As a result, there will always be a place for residual herbicides, but there are a limited number of alternative control products available.

“Utilising a well-planned ICM strategy can lessen the need for unplanned herbicide use, and encourage activities on the farm that support the principles of the stewardship initiative.” Encouraging farmers to apply metazachlor and quinmerac sensibly – at the correct dose rates of 750g/ha and 250g/ha, respectively, for winter oilseed rape, and well in advance of the October 1 deadline for drained land in drinking water safeguard zones – would all help towards retaining them on the marketplace for seasons to come.

Steve Townsend, independent adviser at Soil First Farming, stressed that what is good for soils is good for stewardship.

He said: “The biggest influence we have on soil health is the provision of organic matter in the many forms of carbon it provides.

“Improving carbon levels can support crop establishment, particularly oilseed rape, by allowing the crop to grow fast and compete with weeds.

“Good soil management can result in a much better tilth and seed bed conditions in the short term, allowing for improvements in residual chemical activity.

“While in the long term, better soil structure facilitates soil stability and water infiltration, which both help to keep the pesticide in the field.”

He said increased carbon levels can be achieved through implementation of ICM practices, such as reducing tillage or ploughing depth, which reduces carbon oxidation losses from the soil.

“Organic matter, or carbon, in the soil should be treated like a bank account,” said Mr Townsend.

“You have to put more carbon in each year than you take out if you want to see your soil health and structure improve.”