Blackgrass Control Strategies – The importance of Cultural Control and Residual Stacking

Posted on 13 September 2019

The importance of blackgrass control

For many UK farmers blackgrass is one of the toughest challenges. As few as 10-15 plants/m2 can result in a 5% yield loss in wheat and blackgrass counts of 500 plants/m2 can result in yield losses as high as 50%. Despite some new chemistry on the horizon cereal growers are currently reliant on cultural control and multiple herbicide applications to achieve even moderate levels of control.

Building levels of resistance

Flufenacet often forms the backbone of the blackgrass herbicide programme. Recent testing in the UK and Germany has found reduced sensitivity from blackgrass to this vital molecule. Worryingly those plants with reduced sensitivity to flufenacet were also found to be less sensitive to Prosulfocarb and Pendimethalin, two other cornerstones of many blackgrass herbicide programmes. These shifts in sensitivity make an Integrated approach even more vital. Cultural Control methods must be optimised including delayed drilling, higher seed rates and incorporating Spring Cropping into the rotation. Enhanced Metabolism resistance has also been confirmed in some ryegrass plants in the UK. Where this is concerned the situation is even more serious and will involve significant changes to on-farm practice.

An integrated approach….

James Francis, Norfolk based agronomist with Chemspec East Anglia suggests ‘’When it comes to formulating a blackgrass herbicide programme for the autumn, the use of multiple active ingredients in tank mix or sequence is an important part of product stewardship. This will help achieve a better level of control overall and will also help to avoid a build up of resistance to individual molecules. Since residual herbicide products tend to work better under moist soil conditions timing of drilling and herbicide application is as important as product choice.’’

Clayton offer a complete range of residual products

Clayton Plant Protection offer a full range of autumn residual products for use in cereal crops. At the heart of their portfolio is a range of Flufenacet + DFF co-forms marketed under the brands Clayton Facet, Clayton Sabre and Clayton Aspect. Supporting these are Clayton Tacit (straight Flufenacet), Clayton Obey and Clayton Comply (Prosulfocarb) and Pendifin 400SC (Pendimethalin). This broad range of cost-effective products enables agronomists and farmers to tailor their blackgrass herbicide programmes to suit their individual situation.

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