Continuing mild, wet weather is making field work virtually impossible apart from ploughing on lighter, free draining soils. Crop growth stages have hardly moved on much since my previous report four weeks ago. Both growers and crops are hoping for conditions to improve.
Despite most fields having a useful quantity of nitrogen within the crop, some winter barleys are starting to yellow and will become a priority for top dressing. Doubtless dressings to oilseed rape crops will follow “as the spreader is already on the tractor”. A nitrogen/sulphur product is advisable at this early timing. Prioritising jobs thereafter will be the key skill in this spring’s work.
Annual meadow grass control in un-sprayed wheat crops may become a problem if conditions for travelling across fields do not improve. Once nitrogen is applied to crops, weeds will start to grow rapidly. There may be an opportunity to get on with Liberator (flufenacet + diflufenican) tank mixed with additional diflufenican. However, the chances are that most of us will be defeated by the weather and/or ground conditions; then the only control option in wheat will be Othello (diflufenican + iodosulfuron + mesosulfuron) plus Biopower.
Light leaf spot is beginning to increase in oilseed rape crops, but should be well controlled by a tebuconazole/prothioconazole co-formulation. In addition to disease control this should give a degree of plant growth regulation. If more serious canopy management is required then the use of Caryx (mepiquat + metconazole) should be contemplated.
In the absence of frosts to check foliar diseases, mildew, net blotch and rhynchosporium have continued to develop in winter barley crops. An application of cyprodinil plus chlorothalonil at T0 will more than pay its way. In addition this will take the pressure off the T1 timing when an triazole/strobilurin mix is likely to be the order of the day.
As with winter barleys a T0 application on winter wheat will permit a more precise timing for the T1 spray. This mix should clean up septoria and provide protection against rust and mildew. A strong triazole plus chlorothalonil should be adequate at this timing. Note that no more than 2000 grammes of chlorothalonil can be applied throughout the life of the crop.
This winter, most of my soil samples have revealed a serious shortage of Boron. To ensure full crop potential, this and other easily leached nutrients will require to be supplemented either with fertiliser or more likely through the leaf. Yet another job to be built into the programme.