South: Getting ready for winter wheat drilling

The majority of the harvest is now complete, apart from a few fields of wheat which still remain. With improved weather forecast for this week, the prolonged harvest will, at last, be finished. On the plus side, yields have been good. Winter wheats have averaged about 10t/ha, winter barleys at 7.8t/ha and spring barleys 6.75t/ha, but many spring barley crops have failed the malting quality due to high nitrogen levels.

A lot of rape crops were drilled in the last 10 days in weedy min-tilled stubbles, with a view to spray with a metazachlor-based herbicide and glyphosate pre-emergence. Unfortunately the weather beat us again. The rape seed has chitted and the crop has just started to come through. These fields will now need to be sprayed post-emergence without the glyphosate as soon as the majority of the crop has emerged. Spraying before this stage can lead to crop damage, especially if there is heavy rain on light soils, but spraying later will lead to an ineffective weed control.

Winter wheat drilling will start after the end of the second week of September and winter barley soon after. But before that we will create a stale seed-bed and spray off with glyphosate to reduce the grassweed burden and also the risk of aphid infestation. Before drilling the cereal crop, carefully work out the seed rate based on the 1000-grain weight. Take into account the target plant population, drilling date and seed bed conditions. A low seed rate non-competitive crop can lead to difficulty with blackgrass control. Where blackgrass is a problem, delay the drilling and use a higher seed rate.

In damp cloddy seed beds slugs could lead to serious plant loss. In oilseed rape crops, slugs are already grazing leaves and cutting the off the stems. Before drilling the seed lay layers, mash slug traps in the shape of a W to determine the need for slug pellets. Remember the new guidelines which prohibit the use of slug pellets round headlands next to water and ditches and the maximum dose of 700 grams metaldehyde per field between January and December in any one year.

If you are growing winter barley you really have to be prepared to throw everything at blackgrass control pre-emergence since the post-emergence options are now so limited. I will use Defy/DFF/flupyrsulfuron-methyl (Lexus) mixes at robust rates which worked exceptionally well for me last year.