Sunday, 20 October 2013

SUMIMAX - Redefining autumn weed control in winter wheat

Some broad-leaved weeds are becoming more of a problem with the recurrent use of the same chemistry leading to weed resistance. SumiMax offers a different mode of action with a very wide broad-leaved weed spectrum, without compromising annual meadow-grass control. It can also be useful when stacking residuals against black-grass.

Stewart Woodhead, Technical Manager for Interfarm UK Ltd., points out that we are fast approaching the spray window for annual meadow-grass and broad-leaved weed control in winter wheat.  “But most meadow-grass solutions don’t control important broad-leaved weeds such as cleavers, charlock, groundsel, fumitory, poppy, mayweeds and chickweed that farmers are looking for. Nor do they offer a totally different mode of action on these weeds. SumiMax (flumioxazin) is an effective and different option for annual meadow-grass control, with both contact and residual properties. It excels in its ability to control an unprecedented range of both sensitive and resistant broad-leaved weeds, through a different mode of action to ALS herbicides.”

“Trials and commercial use show that SumiMax performs very well on annual meadow-grass, resulting in 80-90% control when used alone at 100 mls/ha and 90% plus when mixed with a partner herbicide such as Liberator. In addition to meadow-grass, SumiMax provides an excellent range of broad-leaved weeds. In trials, it gave 100% control of charlock, chickweed, cranes-bill, fumitory, field pansy, groundsel, ivy-leaved speedwell, mayweed and red deadnettle, 99% control of cleavers, common field speedwell and Shepherd’s purse and 98% control of poppy. Additionally, users have reported very good activity against volunteer crops, such as beans and borage. No other wheat herbicide performs to this level or offers such a wide weed spectrum,” he reports.

Stewart suggests there is a potential position for SumiMax for black-grass control in wheat as part of the residual stacking programme. In trials SumiMax has added around 20% control, that coupled with it good broad-leaved weed spectrum, and alternative mode of action makes it a useful partner in the fight against black-grass. Interfarm is conducting a series of black-grass trials sites this autumn to demonstrate these benefits.

One particular advantage of SumiMax is that it is very straight-forward to use and can be easily integrated into any herbicide programme.  “It has no complications or restrictions when it comes to its application. It can be sequenced with any product including any sulphonylurea herbicides, but a 14 day interval should be allowed when sequencing with other herbicides. It is compatible with a wide range of autumn products, but should not be mixed with adjuvants, pendimethalin or prosulfocarb post-emergence. It has no following crops or cultivation restrictions, which make it easy to integrate with other autumn or spring-applied herbicides,” says Stewart Woodhead.

Stewart explains that flumioxazin can be applied post-emergence up to before GS 15, which is when the crop has 5 leaves on the main tiller.  “In practical terms this means that SumiMax can be used post-emergence throughout the autumn and winter during tillering of the crop, the usual window for meadow-grass control. The limiting factor is usually the size of the weeds, which need to be small at time of application.”

He also advises that crops must be sufficiently hardened off.  “From the PPO inhibitor group, SumiMax has strong contact activity as well as residual activity. Crops need to be reasonably hardened off to reduce any risk of foliar spotting. I would warn off treating soft crops, lush crops, waterlogged crops or crops under stress with SumiMax.”