The mixed weather and below average temperatures have certainly made things difficult for both arable and grassland farmers recently. We have almost accepted there is no such thing as the norm anymore. It has been very frustrating for farmers trying to grab every available opportunity to spray crop as ground underfoot has become very soft. Conditions however have been ideal for weed control onto potatoes and veg as residual herbicides require moisture to work effectively.
SPRING CEREALS
The above average rainfall over winter has depleted many soils and it is essential to replace essential nutrients. Spring barley crops grown on low PH soils with a low P index seem to be struggling most this season. This must be rectified with lime and Phosphate fertilizer in accordance with soil analysis.
An application of a balanced and rapidly available source of macro & micronutrients at this key time will minimise the adverse effects of restricted soil nutrient uptake. CEREAL HIGH N supplies 3.7%Mn, 1.5%Mg, 1.8%Cu, and 0.6% Zn in the most rapidly available form to the plant through the leaf and also supplies high levels of Nitrogen and Sulphur.Potash deficiency is also showing up in many spring barley crops with pale green yellow tips being the first symptom.Deficency is most likely on light sandy soils or in crops following intensive grassland. Manganese deficiency is also appearing on crops especially those in a continuous cereal regime or where lime has been applied recently. A foliar application may be applied along with the weed control.
To minimise the effects of competition on the crop and optimise the level of weed-control, herbicide application should be carried out at the earliest opportunity, once all the weeds have emerged but are still small, and before they begin to compete with the crop for nutrients and light. With low soil temperatures since drilling, weeds are not coming through as rapidly as expected but chickweed is beginning to choke out young plants and must be sprayed as soon as possible.
Product choice will depend on the weed type and size present and the crop growth stage. Broad leaved wise, Sulfonyl-urea (SU) herbicides will likely be the starting point, controlling a wide range of weeds and very safe to the crop. ALLY MAX covers a wide spectrum of BLW with the max formulation giving improved control of polygonums & other BLW over the old ALLY formulation. HARMONY SX controls a wide range of BLW at sizes larger than any other SU. However they must always be tank-mixed with another BLW herbicide to control SU resistant weeds (chickweed) and those weeds not controlled by the SU’s (cleavers, fumitory& fat-hen). Ideal partners are COMPITOX controlling (chickweed, fat-hen, fumitory), and SPITFIRE /MINSTREL for chickweed and cleavers. HUSSAR may be applied to spring wheat and spring barley to help control annual meadow grass.
Where the range of BLWs present are limited to chickweed, redshank, fat hen, fumitory & day nettle, the hormone mixture products, such as Mircam Ultra, will work well without the need to tank-mix, but must be applied by GS31. Where the likes of field pansy, forget-me-not, speedwells & corn-marigold are also present, sulphonyl-urea products will improve control. AXIAL gives excellent control of wild and tame oats in spring barley and spring wheat and has an excellent window of opportunity. Application should be held off until at least 6 weeks after drilling to ensure all wild oats have germinated. It can then be applied up to full flag-leaf of the crop and full flag leaf of the wild oatGS39, allowing a minimum of 21 days to have elapsed after application of the BLW herbicide. The wetter ADIGOR must be used in all situations along with the AXIAL.
WINTER WHEAT
Most crops are now at flag leaf with Septoria tritici present in most crops at variable levels depending on T1 timing but with recent weather expect levels to rise if fungicide rates and timings are not correct. Mildew is present on almost all winter wheat varieties and a morpholine based product should be applied to clean up the crop. The inclusion of Talius in the program will give very good persistent control of mildew. Of all fungicide treatments, T2 has the greatest impact and response in terms of grain yield and quality, keeping the top three leaves clean and the ear as it emerges. The dose rate applied must be sufficiently robust to ensure long term protection of the flag leaf plus eradicate disease already present on the lower two leaves that also contribute to yield. Epoxiconazole & metconazole in mixture(BRUTUS) will form the key part of the T2 fungicide onto winter wheat. SDHIs are now regarded as essential partners to maximise the yield of all crops with any reasonable potential, with the most responsive timing for the newest SDHI molecules being at T2. Products such as PEXAN or AYLORA/PROSARO mixtures are ideal for use at the T2 timing. Growth regulator (CERONE)must also be applied at this time where required.