Concerns over propyzamide being found in watercourses has prompted new research from Dow Agrosciences.

According to the maker of Kerb Flo the area treated had increased and growers were using higher doses to achieve effective control of blackgrass.

“We need to show a reducing presence in watercourses,” said the firm’s David Roberts. “If we don’t the risk is that it will be actioned by regulators.”

Research sites had been set up to measure the effect different cultivation measures and the use of buffer strips had on run-off, he said.

“We have had no official results as yet, but we have found that surface run off can be reduced by as much as 80% using 6m grass buffer strips.”

Results from the first year’s experiment would be available later this year and work was continuing with trials at Newcastle University’s Cockle Park Farm, said Mr Roberts.

“We want to see the effect of planting different crops in the buffer strip and work out the optimum width for a given slope,” he said. “We will also look more at the effect of plough, min till and direct drilling.”