Many of us witnessed horrendous weather conditions over last weekend and any urgency to tend crops has been further delayed. Both grass weeds and broad leaved weeds are appearing in crops which did not receive an autumn herbicide. Wheat crops are still showing low levels of disease whilst most winter barley crops have a fair bit of foliar disease on older leaves.
Cereals
Much of the later drilled winter cereal crop did not receive a residual herbicide. As temperatures rise clods will be broken down on both treated and untreated crops requiring a herbicide treatment. Those wheat crops not treated in the autumn can be treated with OTHELLO and BIOPOWER up to GS32 of the crop. Applications should be made when temperatures are good and both the crop and weeds are actively growing. OTHELLO will give good control on chickweed, pansy, speedwells, charlock, groundsel and most importantly annual meadow grass. I have spotted a few wild oats over the last week but it is important to note they will continue to emerge over the coming weeks and treatment should be delayed until all of the wild oats have emerged. AXIAL and ADIGOR can be applied from GS11 up to GS39 on both wheat and barley. Where weed control is required a 7 day interval must occur from the time of spraying Axial before applying sulfonyl urea or hormone herbicides. If these products are applied first then a 21 day interval must be observed before applying Axial.
Preparing For Spring Crops
Land intended for spring cereals should be sprayed off with glyphosate as ground conditions allow. Roundup Energy is still the best value for money in the glyphosate market with all its additional benefits over generics. Roundup Energy has faster uptake and greater consistency in a wider range of weather conditions. It is important to remember when comparing glyphosate prices the amount of active it contains, Roundup energy contains 450gm/l compared to 360gm/l in most other glyphosate.
The slight increase in day time temperature over the last week will encourage pests such as wireworm, slugs and leatherjackets to resume feeding and should be closely monitored. Surveys carried out recently show leatherjacket numbers are significantly higher than spring 2012.Pre ploughing treatments with Dursban or Cyren are more effective than those applied once any damage is under way in the spring-sown crop.
Disease Control
In our climate maximising yield means controlling disease effectively. Getting timings right is absolutely essential; ‘fire-brigade’ control of disease is more costly and a lot less effective than well timed preventative control. Except in very low disease pressure conditions, it is a false economy to skimp on disease control and get away with it – all independent work shows that increasing fungicide doses does also increase yield.
Manganese deficiency is now commonplace in many crops, symptoms showing as growth gathers pace. Continuous cereal ground and ground recently limed is most prone to deficiency. Symptoms begin with small pale green speckles appearing throughout the leaf and these will progress to turn brown unless treated.
Copper deficiency often accompanies Mn deficiency – its symptoms are complete browning of the leaf tip especially the youngest leaves, and apparent wilting of the plant. Treatment will be most effective if treated as soon as symptoms are seen.