Agrii agronomist, Matthew Clark, believes the addition of adjuvant Backrow to the residual mix of herbicides has an important role to play in improving herbicide performance.

“We’re loading chemistry at the pre-emergence and peri-emergence timings to get control of black-grass. Residual stacking can pose a threat to crop safety if rain leaches the herbicides down the soil profile into the crop’s rooting zone. Backrow helps retain the residuals in the top 5cm, the weed rooting zone, which is where they’re needed to work effectively.

A crop that hasn’t been knocked about by herbicide will be healthier and more competitive against germinating weeds, but Backrow has other advantages which translate into an increased level of black-grass control.

We need to get 98% control of black-grass to stop the problem from escalating and that’s not easy to achieve, every little bit helps. We’ve looked at adjuvants extensively in Agrii trials and have found Backrow contributes an average of 9% increase in black-grass control when it’s added to residual herbicides.

Backrow is a drift retardant, but this feature alone doesn’t fully explain why it’s consistently improved herbicide performance in the field. It also has the ability to increase the uniformity of spray droplets to produce a more predictable spectrum, giving improved deposition on the soil surface. This better coverage of the soil means more germinating weeds come into contact with the pre-em herbicides at emergence, which helps account for the increase in efficacy seen in trials. You could say Backrow is helping eek out every last ounce of activity from the herbicide.”


Backrow is a useful addition to the tank with pre-em herbicides for winter beans. Again we’re loading the crop with pre-em residuals for blackgrass control. It’s really important to hold the herbicide in the top 5cm for as long as possible in a crop that’s not very competitive and can be sensitive to the phytotoxic effects of some herbicides.

Matthew Clark, Agronomist, Agrii