West: BYDV a potential threat in south-west this autumn
Since last writing autumn plantings have moved on at a fair pace. With an earlier and drier harvest than recent years the drilling of cereals started earlier than in the last few autumns. This combined with higher than usual September temperatures and adequate moisture for germination, has lead to very rapid emergence and establishment of many crops.
Many winter barley crops were emerged within five to six days of drilling. Even where Deter (clothianidin) seed treatments have been used there will almost certainly be a requirement for a follow up application of aphicide to keep barley yellow dwarf virus (BYDV) under control. Due to the shortage of Deter seed treament this year there have been a number of crops that have been drilled relatively early, but with no aphicidal seed treatment.
These crops must now be considered to be at high risk from BYDV and should receive an aphicide application at the earliest opportunity and will probably require a second application if the weather remains relatively mild. The winter of 2011/2012 was similar to the way this season is developing, but crops were not drilled quite so early. BYDV proved to be a serious problem in spring 2012 and I believe it is fair to assume that this year the problem can only be worse due to the earlier drilling and warmer temperatures.
Oilseed rape crops have established well, with nearly all crops now having a larger biomass than last years crop was managing during March. Potential for this years crop should therefore be better than the 2012/2013 crop. Most crops have now received a graminicide to control volunteer cereals and at the time of writing – with a good weather window – many crops are just receiving a fungicide for the control of phoma and light leaf spot.
Winter wheats currently range from being well established to not yet planted, where following a later harvested break crop such as Maize. Where crops have been drilled early and are well established BYDV will again be an ever present risk this atumn, particularly on farms with coastal proximity. Most crops have been treated with a pre-emergence herbicide unless there has been a good reason to leave the crop and treat it later with an early post-emergence treatment. With a more normal area of wheat planted this autumn compared to last year, wheat seed supply is now beginning to get a bit tight, with quite a few varieties now sold out. If any grower has not yet secured wheat seed for this year, he should do so without too much delay.
Forage maize has enjoyed a much better growing season than the last few years and crops have reflected this, with some very useful yields being returned. Quality looks like it will be good this year too, as most crops have produced some very large cobs. Many crops have responded well to a pre-tasseling treatment of the foliar applied nitrogen product Efficie-N-t 28. There have been visible differences in cob size between treated and untreated areas of crops and early yield assessments would indicate an increase in cob yield of up to 30% from the treatment. It has been recognised for some time that maize responds well to nitrogen applied at, or just before tasseling, but finding a safe and easy to apply product has been an issue. This product would appear to be the answer.
With the weather still onside and ground conditions still good I hope that we may soon see all the planned winter crops in the ground and safely established.