THOSE with winter oilseed rape will have a new broadleaved weed herbicide at their disposal this spring – and it's a step-change up from some old favourites.

Korvetto, from Corteva Agriscience, is said to have excellent activity on the weeds that steal yield and cause issues at harvest time – like cleavers, mayweed and thistles. However, it also has good activity on a broad range of other problem weeds, including cranesbill and poppy.

It contains Arylex Active – the same active ingredient used in the recently launched autumn herbicide, Belkar – this time in formulation with clopyralid.

Corteva’s oilseed rape category manager, John Sellars, said: “Even farms which apply good autumn herbicide programmes in a timely manner will usually face a late winter and early spring-germinating broadleaved weed burden. Korvetto will be a good option for UK farmers because it will control many of the weeds found in oilseed rape crops as daylight hours increase and temperatures rise.”

Until now, Corteva’s Galera (clopyralid + picloram) has played a leading role in most spring-applied oilseed rape herbicide programmes for many years, but Mr Sellars said Korvetto represents a step-change in performance.

“Both contain clopyralid, but Korvetto is significantly beefed up by the inclusion of Arylex – the unique herbicide molecule which is being introduced into a number of crop sectors. This allows farmers to cover a wider spectrum of weeds while gaining a higher level of control.”

The application window mirrors Galera – March 1 to growth stage BBCH50 (flower buds visible above the crop) – but the added strength in the formulation means it strong activity on those familiar ‘red-faced weeds’ that become visible above the crop as the season progresses.

There are no following crop restrictions and it can be used even if a post-emergence herbicide, like Belkar or Astrokerb, were used in the autumn.