Hutchinsons will be offering growers a new blackgrass susceptibility testing service with a laboratory partner that should give results by the end of September, just in time to help pre-emergence herbicide decision making.

The effectiveness of partner herbicides for flufenacet against blackgrass seems to vary widely between sites, says David Ellerton, Hutchisons’ technical development director. “At some sites pendimethalin is effective, or prosulfocarb, or diflufenican, or extra flurtamone, for example.”

Testing blackgrass seed from the previous crop, or a block of fields which have had a similar treatment history, for susceptibility to those active ingredients could potentially help growers pinpoint which partner to use next season, he explains.

“For example, last year we did six tests, three of which showed susceptibility to prosulfocarb and three were not. It helps give guidance where an active could give good results.”

Seed needs to be collected when mature by shaking ripe seed from heads, rather than stripping, he stresses.

The pot test will cost around £120 a sample for tests against multiple active ingredients.