Having spent a winter hearing and speaking about all that is gloomy in agronomy such as lost actives, pesticide resistance, building disease pressure and falling crop prices, I am looking forward to getting stuck into the field walking and tackling the season. However, in these wet conditions the wheels aren’t turning.
Optimistically, it will dry out soon and we can start to chip away at the spring workload, meanwhile wet days provide an opportunity to complete nitrogen and sulphur plans and to firm up the spring spray strategies.
The mild, wet weather has meant that crops and diseases have continued to grow during winter. Many crops have good yield potential, but the early season fertiliser and sprays will need to be well planned to manage early growth and disease development. Early drilled wheat crops are showing a high incidence of septoria and in susceptible crops rusts are easy to spot. The winter conditions may also have encouraged eyespot although the severity of infection will also depend on weather conditions in early spring.
Wheat varieties that are more susceptible to yellow rust (e.g. Kielder, Santiago, Solstice), should be checked for yellow rust. From my observations on susceptible varieties I will be encouraging a cheap triazole spray as soon as conditions allow. On less susceptible varieties fungicide control will start at the more usual T0 at early stem extension (usually mid-March).
Rapeseed crops can be checked to see how well autumn sprays have worked and whether a spring herbicide for thistle, mayweed or cleaver control will be required.
Nitrogen and sulphur plans are in place and winter rapeseed, later-drilled wheats (mid-October onwards) and winter barleys will receive their first fertiliser dose towards the end of the month, assuming conditions are dry and mild enough for active growth.
Aphid migration continued into early winter so it would be worth checking that all cereal crops were protected against barley yellow dwarf virus (BYDV) infection by seed treatment and/or foliar sprays into mid-November. As a precaution it could be worth controlling any overwintered populations in “at risk” crops before colonies expand and spread the virus in early spring. Another job is to treat crops prone to manganese deficiency; some autumn treated crops are already showing new signs of deficiency.
Wheat bulb fly risk is relatively low this season and egg hatch is late. However, “at risk” crops should be monitored carefully and treated as necessary. Later at the dead heart stage, rolling and early nitrogen can be used to reduce the impact of this pest.
Regarding black-grass, results from autumn residuals have been mixed; in some situations the strength of the black-grass population is scary. Post-emergence grassweed herbicides such as Atlantis (iodosulfuron + mesosulfuron), can be applied when soils warm and the crop and weeds have been actively growing for about four days. Check the Atlantis spring tank mix label for compatible mixes.
Growers will be eager to start seed-bed cultivations and drilling. Remember that good seed-beds are often more important than calendar date, so it may be several days or even weeks before some fields are dry enough for action.