West: Recent frost has little effect on forward oilseed rape crops

The first frost-free morning for three weeks may signal the start of spring and the time to assess crops coming out of winter.

The lush growth of some crops prior to Christmas has been knocked back, but in general cereal crops still look good and well-developed.

Winter barley that had very dense growth in autumn was, in some cases, badly infested with mildew and probably should have had a fungicide treatment. The frost that would usually suppress the disease took a long time to arrive. These crops may need a T0 treatment in March to stop the disease from developing.

There are many thick oilseed rape crops in the region on which the frost appears to have had little affect and pigeon damage has so far been minimal. Their Green Area Index is already high and will need careful assessment later to make decisions on nitrogen rates and growth regulation.

Charlock in rape needs assessing to see if the frost has killed it. If not, the only option for controlling it is bifenox, which gives variable results.

Application of blackgrass post-emergence treatments in wheat was a stop/start affair before Christmas. A lot was applied, but many growers were waiting, first for blackgrass to emerge and then for suitable ground conditions. Once blackgrass growth starts again, this spraying will be a priority.

Spring drilling has started, with beans and spring wheat going in on the frost. There are few options for post-emergence weed control in beans so a pre-emergence treatment is essential.

Pre-emergence spraying should be considered for spring barley also, particularly if meadowgrass is likely to be a problem.

See more