Corteva Agriscience has two new herbicides to help farmers tackle buttercups in their grass fields this spring – ProClova and Thistlex Pro.

Buttercups will reduce dry matter (DM) grass yield and if eaten in quantity, can lead to reduced dry matter intakes in cattle and sheep.

This is because buttercups contain ranunculin, which converts to an irritant substance when plant material is damaged due to chewing. This can lead to excessive salivation and drooling and blistering on the lips, tongue and gums. It can also cause digestive upset.

 Buttercups lose their toxicity when they are dried, so are less of a problem when found in hay and silage. The greatest risk is associated with grazed pasture.

 Envy has been the traditional product of choice to eradicate buttercups but has to be applied when the plants are young, with new green growth and before flowering. Stock need only be removed from the sprayed field for seven days before returning and there are no special manure management requirements. This means it can be used on fields that will be cut for silage and hay. Envy will however kill clover.

 Where clover is an intrinsic component of the sward, ProClova XL can be used as this will kill buttercups. This product launched last year, offers highly effective clover-safe weed control for use in new sown leys and established grassland.

 It is best to spray before the buttercups have flowered and when overnight temperatures are forecast to be above eight degrees centigrade for three days before, and three days after the proposed application date. ProClova XL can be used on grazing and cutting ground.

 Where there are long established populations of buttercups or where circumstances mean they are flowering before the sprayer gets to the field, consider Thistlex Pro, a new herbicide launched by Corteva this year. It is highly effective in these situations.

 This gives outstanding control of both creeping and meadow buttercups; the most common buttercup species found in the UK. When spraying weeds that are in flower, treat early in the morning or late evening when less pollinators are present.

 Grass treated with Thistlex Pro must not be cut for fresh grass, hay, haylage or silage within 12 months of treatment.

 For more information on Corteva grassland herbicide products visit www.Corteva.com/uk or download the Corteva Forage app, available free from the app Store.