South: Slugs play havoc

Drilling is about halfway through, but remaining ground will not be drilled until we have four to five days of dry weather. The late September-drilled wheat is at the one to two leaf stage, but everything else is still below ground.

Slugs have started to play havoc in some fields planted after oilseed rape. Where they are damaging the crop, apply slug pellets but take into account the new guidelines for Metaldehyde-based products. In my experience Methiocarb slug pellets work better in wet conditions.

Flufenacet is the best residual grass weed material available as it is least affected by the resistance issues, but needs to be sprayed as early as possible before the weeds get large. Sterile brome is another difficult weed to control especially in barley. Where this is the case a good programme is to sequence flufenacet + pendimethalin with Avadex (Triallate).

Oilseed rape crops range from two to six leaves and are well established in warmer soils with adequate moisture. There are a large number of cereal volunteers and blackgrass plants present and some fields will need spraying for the second time.

Remember that the same active ingredient may not be sprayed twice for the same target; use a different molecule if there is a need to spray again.

Look out for peach potato aphids that transmit turnip yellows virus as seed dressings will soon be running out of steam. Turnip yellows virus that has symptoms of reddish purple mottling on the leaf, and looks a little like phosphate deficiency can lead to devastating yield loss.

Losses of 20% to 30% are not uncommon. Pyrethroids, such as Markate (Lambda-Cyhalothrin), give good control; the latter also takes care of resistant aphids which are steadily becoming more prominent.

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