Unusual weed species are being spotted in winter cereals which is causing concern among growers and agronomists, prompting questions about whether typical spring herbicide programmes will be effective this spring.

Hazel Blanshard, product manager at FMC, said:“Willowherb, corn spurrey, lesser celandine, and coltsfoot are being reported as unexpected and out of place this year. Volunteer beans, while not that uncommon, are also causing problems, as are larger than expected populations of groundsel.”

“The reasons we’re seeing greater populations of these weeds is threefold. Firstly, the lack of autumn residual herbicides applied in some areas; certain weeds favouring germination in wetter soils, and finally, the relatively high soil and air temperature over the winter.”

The Scottish Farmer: Willowherb has been found as one of the unusual weeds amongst winter cereal cropsWillowherb has been found as one of the unusual weeds amongst winter cereal crops

“Most of these can still be successfully controlled with metsulfuron based products, with better and more consistent control achieved with metsulfuron and thifensulfuron, or metsulfuron and tribenuron co-formulated products.”

For those who are tackling volunteer beans, Ms Blanshard recommends tank mixing SU herbicides with a hormone herbicide to provide better control of the bigger plants.

“If weeds are large by the time you come to control them, using higher dose rates is advised,” she says.

“Maintenance of water rates and correct nozzle choice, combined with a reasonable forward speed should always be a high priority, but this year it may also be key to achieving best results."