Most growers appear to have adequate rain at this point and some have too much. Ground conditions continue to prevent the completion of field work across parts of the west and northwest, where crops remain to be sown.
Warmer days and the evaporation of rain add to disease risk. While most winter barley crops remain very clean and virtually free of disease, protection is still important and ongoing showers make timely spraying difficult. Mildew becomes an additional risk in this type of weather. Virtually all crops have picked up in colour as growth rates sped up and more backward crops raced through growth stages.
Crops have generally remained clean thus far but septoria can be seen oozing spores in wheat crops so new lesions can be expected soon on unprotected leaves. Most crops are now at flag leaf emerging to emerged and so it’s time for T2 once the flag leaf is unfolded.
While crops are largely clean, T2 fungicides are still very important as we are likely to see a lot of pressure build now in this broken weather. Some crops will have received a strong product at T1, but this treatment still needs a strong mix of Triazole/SDHI (Librax, Adexar, Ascra, Elatus Era etc) or one of the newer actives – Revystar XL/Lentyma or Questar plus prothioconazole.
Try to change the actives, especially the azole, between T1 and T2. Protecting the new products should always be a priority so add folpet to the tank with the other fungicides.
Consider 40-60kg N/ha on winter wheat post GS39 depending on field history, the potential of individual crops, the amount of N already applied and the appearance of the crop.
Crops have moved rapidly to various stages of late booting to earing out and so it is time for final fungicides. Most crops remain clean with healthy leaves to the ground in the short canopies that have stretched considerably in recent days. This crop is more up and down than any other but hopefully it will level off post earing out.
Spray at the early stages of awn/ears emerging to get the contact spray (folpet) on in good time to help protect against ramularia. Crops have endured a lot of stress so infection risk must be high. The only foliar disease I have seen in crops in recent days is septoria nodorum.
All treatments must have folpet included alongside the main actives to help against ramularia. Options include Ceriax, Elatus Era, Fandango, Macfare Xpro, Mandarin Xpro, Opera, Revystar XL, Variano Xpro and Siltra Xpro, or mixtures containing prothioconazole and an SDHI or strobilurin.
Spring barley: Most crops have recovered the symptoms of early magnesium deficiency and have shown good growth over the past week. Early crops are at GS31 and should have a fungicide applied. Herbicides need to be applied. Early crops are unlikely to need aphicide and later crops would still not be a certainty for it either. Crops only become safe after they have covered the ground, so watch local temperature versus crop growth.