Orders for Korvetto, a unique post emergence herbicide for forage brassica crops, have taken off in recent weeks as farmers latch onto its benefits, particularly quick plant-back intervals for following crops.
 

Korvetto comes from Corteva Agriscience, Agriculture Division of DowDuPont, and New Zealand is the first market in the world to register it.
 

Corteva Agriscience’s NZ marketing manager Glen Surgenor says Korvetto is a welcome addition to the company’s comprehensive brassica product portfolio, which also includes T-MAX and Radiate herbicides, and Sparta and Transform insecticides.
 

“Forage brassicas are so important in our farming systems – disappointing yields are not just expensive in terms of return on investment in the crop itself, but also because of the cost of replacing that lost dry matter with something else to prevent subsequent feed deficits, especially in the middle of winter.”
 

Having the choice of three different postemergence herbicides gives retailers the opportunity to fine tune their recommendations in line with farmers’ individual crop protection needs, he says.
 

Korvetto, for example, which combines Corteva Agriscience’s new active Arylex with the trusted chemistry of clopyralid, has an ideal fit with clients who want more room to manoeuvre in their rotation planning.
 

“It’s the most flexible post emergent herbicide for brassicas, with a three month plantback for clover, and six month plant-back for fodder beet.
 

“This gives farmers a lot more freedom when planning ahead for subsequent crops. Some other herbicide options have plantbacks of up to 12-24 months.”
 

A typical scenario where comparatively quick plant-back would be of real benefit might be summer brassicas, followed by new ryegrass/clover sown down in autumn.
 

As well as controlling key forage brassica weeds like fathen, nightshades and Californian thistles, at one litre per ha, Korvetto

provides best-in-class control of shepherds purse and fumitory, he adds.
 

Crop safety is excellent for leafy and bulb turnips, kale, forage rape and swedes.
 

Handling benefits include an in-built methylated seed oil (MSO) adjuvant, so there’s no need for farmers to add a surfactant to the mix, and a low odour NeoEC formulation.
 

T-MAX meantime comes into its own for farmers who need to control certain challenging weeds in their crops, such as spurrey, willow weed and amaranthus, and whose rotation planning is not affected by its longer plant-back times.
 

The aminopyralid-based herbicide remains a go-to option for many South Island farmers because spurrey can be such a problem in their crops, and is also particularly effective against docks, giant buttercup, black nightshade, fathen, ragwort and
thistles.
 

Radiate, which is a mix of clopyralid and picloram, has a narrower weed spectrum than either Korvetto or T-MAX, but continues to fill a useful role as a low-cost herbicide option when customers need to get rid of fathen or black nightshade in their brassica crops.
 

All three herbicides can be mixed with either Sparta or Transform as required for IPM friendly insect protection.
 

Sparta (spinetoram) controls diamond back moth and white butterfly caterpillars, looper caterpillars, leaf miner and springtails; Transform (sulfoxaflor) controls aphids.
 

For more detail contact your Corteva Agriscience NZ territory manager.