An extension of authorisation for minor use for Avadex Excel 15G (tri-allate) for use on spring wheat has been given to NIAB by the Chemicals Regulation Directorate.

The EAMU is welcome news for growers as spring crops represent a very important non-chemical approach to grass weed management and can be a particularly successful component of black-grass management on farm. Avadex Excel 15G, the granular form of the herbicide, can be applied pre-emergence of weeds and the spring wheat crop at 15 kg/ha.

“Field trials have shown that black-grass emergence can be reduced by 90% by planting spring wheat rather than winter wheat. Black-grass plants in spring crops are also less vigorous than those emerging in the autumn,” says John Cussans, NIAB’s weed specialist.

“However, for these spring crops to be a successful component of grass-weed management through a rotation we can’t rely entirely on spring establishment timing. Although there is a reduction of grass-weeds in spring crops it’s not 100%, so growers also need an effective and diverse range of herbicides available for use. This EAMU for Avadex granules in spring wheat is part of NIAB’s ongoing process to try and ensure that farmers have as many tools to control grass-weeds in spring crops as possible.”

Dr. Dominic Lamb of Gowan reports that more growers are successfully using Avadex Granules in their winter crops and he anticipates an upsurge in usage in spring crops, too. 

“Avadex adds to the overall control of difficult grass-weeds such as black-grass, annual meadow-grass and wild-oats as well as some common broad-leaved weeds including cleavers, charlock, chickweed, mayweeds and poppy. This EAMU for spring wheat joins the already long list of spring crops on the Avadex label including spring barley and sugar beet and its other EAMU’s including spring linseed and spring rape,” says Dr Lamb.

Spring crops may also become more common following the introduction of new crop diversification rules as part of CAP reform requiring most farmers to grow at least three crops.