Conditions are just right for post-em Digital

Frosts have been recorded in most parts of the country now and wheat crops will be hardened off sufficiently for the post-emergence application of the contact and residual acting herbicide Digital, according to Dr. David Stormonth, Technical Manager for Interfarm UK Ltd.

When soil is moist, the weather is cool and weeds are small, then conditions are at their best for the control of annual meadow-grass and difficult-to-control broad-leaved weeds such as cleavers, groundsel and poppies. “It is also the time when growers are used to applying an herbicide for these weeds. In the past this slot was when IPU was normally applied. This year the spray window may be a little later than normal, but the prevailing conditions now are spot-on for effective weed control combined with good crop tolerance.”

Dr. Stormonth reports that in trials and commercial use Digital (flumioxazin or FMX) performs very well on Annual Meadow-grass, giving 95% control on average, much more consistently than IPU ever did. “For what I would call a ‘normal’ Annual Meadow-grass population, Digital can be a stand-alone option. If weed populations are more challenging, add in a very low rate of just 0.1 l/ha of Liberator, which will raise control levels from 95% up to 100%. Or you can mix with a low dose of a chlorotoluron containing product if growing a tolerant wheat variety, but be careful to avoid any risk to watercourses. You can add in a pyrethroid, such as Sven, for BYDV prevention as seed treatment insecticides would have run out of steam by now. A word of advice though â€" when applying Digital make sure that you start with a clean tank and finish with a clean tank. It is surprising how much residue of other products can be found in spray tanks from previous applications.”

When it comes to broad-leaved weeds, Digital has by far the widest weed spectrum of any current autumn wheat herbicide. “Weeds such as poppy, groundsel and charlock used to be easy to control but we’ve lost that chemistry, whilst other common weeds such as chickweed and mayweed continue to be a problem. In trials, Digital applied early post-emergence gave 100% control of charlock, chickweed, 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.”

David says that by now crops should be sufficiently hardened off for post-em treatments. “Unlike most autumn applied wheat herbicides, Digital has both strong contact activity and residual activity. Crops need to be reasonably hardened to reduce any risk of foliar spotting. Given the recent cold spell and frosts, most crops will be tough enough by now. Obviously crops under stress for any reason should not be treated, though.”

“Some growers may not be aware that the cost per hectare of Digital has been adjusted to make it more cost-effective, particularly for growers with meadow-grass and broad-leaved weeds. So it is well worth using it and finding ways of integrating it into your weed control programme,” says David.

Digital contains 300 gm ai/litre flumioxazin, formulated as a white, non-staining, easy-to-use suspension concentrate, packed in a 500 ml pack. Recommended in winter wheat, it can be used pre or post-emergence up to before GS 15 for the control of a wide range of broad-leaved weeds, including charlock, chickweed, cleavers, common field speedwell, common poppy, field pansy, fumitory, groundsel, ivy-leaved speedwell, mayweed, red deadnettle and Shepherd’s purse, and grass-weeds, including annual meadow-grass and loose silky bent. It is recommended at 100 ml/ha in 200 litres of water, with one application per crop. It has residual and contact activity. It should not be mixed with any adjuvants or with pendimethalin-containing products. Don’t forget the use of a proprietary tank cleaner before and after spraying to thoroughly clean all spray equipment, including booms, pumps, filters and lids.