Weed control portfolio in oilseed rape extended at crucial time

UK - March 05, 2004

This spring winter oilseed rape growers have a new product to tackle difficult weeds with the launch of Galera* from Dow AgroSciences.

Last autumn’s exceptionally dry weather may have impaired the efficacy of applied pre-emergence herbicides so Galera gives a new, much-needed, post-emergence weed control option that will suit many growers.

“Galera is a post-emergence herbicide for winter oilseed rape. It offers excellent control of mayweeds, sow thistle and creeping thistle,” says Dow AgroSciences’ broad-leaved crop products marketing specialist Donald Westwater.

“But the added bonus is cleavers activity. We have seen an average of 80% suppression in the field. With the recent withdrawal of post-emergence oilseed rape herbicides like Galtak from the market, Galera will be a valuable new tool in the spring weed control program.”

The herbicide, with active ingredients clopyralid and picloram, is approved for use on winter oilseed rape and will be available in early March. As well as its spring use, Galera can also be used in autumn so offering timing flexibility.

Galera offers higher levels of mayweed and sow thistle control than Dow Shield^† , with some control of larger weeds, particularly in the spring.

“Galera controls some very difficult weeds,” says Mr Westwater. “Set-aside and a shift away from phenoxy herbicides mean increasing sow-thistle populations, exacerbated by windblown dispersal of seeds. It is one of those emotional weeds that growers don’t want to see over the top of the oilseed rape canopy, but also produces immense logistical difficulties when it comes to harvesting as sappy stems slow harvesting and clog up combine sieves.

“In a recent company survey, independent agronomists have classed cleavers as the second most important weed to control in oilseed rape. Blackgrass was top. Over three cleavers plants per m² can cause yield losses of over £110/ha, either because of crop competition or through harvesting problems. And that’s before admixture penalties,” says Mr Westwater.

Galera can be applied to winter oilseed rape from the four leaf stage up to before flower buds are visible above the crop canopy. Better weed control will be achieved under warm growing conditions, especially when timed to make the most of the complementary effects of crop competition.

^† Trademark of The Dow Chemical Company