Bur chervil is becoming a problem weed on many farms.
NIAB’s weed expert, John Cussans says if allowed to get ahead of the crop, by May it can have as much of an impact on crop performance as black-grass.
“Our strategy is to identify the weed spectrum in May and June when they are flowering and then implement an appropriate herbicide strategy throughout the rotation using a combination of cultural and chemical control options.”
Broadleaved weed control must start in the autumn with a post emergence herbicide such as Zypar (florasulam + halauxifen), followed up with an appropriately timed spring SU when the temperatures have risen enough to encourage active growth, says Mr Cussans.
“It is a simple strategy which works. For too long, growers have been applying good chemistry at the wrong timing. The answer is to bring timings forward whether that is in the autumn or the spring. And it may be that the optimum herbicide timing in the spring does not coincide with that for fungicides.”