At the time of writing only a handful of fields have been planted to oilseed rape and the harvest is a long way from being finished. As elsewhere in the UK the 2012 harvest is going to be one to forget, with the lowest yields and poorest quality I can remember in over 30 years of doing this job.
The only constant in the wheat harvest is that farmers are universally reporting that any field that was grazed by rabbits over the winter and early spring has been the best yielding, with better grain quality. It seems a major paradox that this pest, that annually costs UK agriculture £millions, should actually have helped in what I am sure will turn out to be the worst harvest in living memory.
The reason for the better performance from these fields is I think two fold. The first contributing factor is that overwintered foliage was eaten off, taking with it much of the rust and Septoria infection, thereby delaying and reducing the development of these diseases.
The second is that these crops were later coming into ear and had slightly less in the way of rainfall during the flowering period, thereby suffering less from fusarium ear blight than the earlier heading crop.
Yields of wheat have been very variable with the best only just moving into the “acceptable” category if being judged against other years. The worst have been an unmitigated disaster. As widely reported already the main factors affecting yield this year have been: 1. Drilling date. 2. Varietal choice. 3. Soil type. 4.Place in rotation. 5.Number and timing of fungicide applications.
It is my feeling that the most important of the fungicide inputs this year was the T0, as without it the battle against Septoria was already lost before the T1 timing. The other trend that seems to be emerging as the harvest progresses is that specific weights appear to be higher in crops that had 2 SDHI applications, with crops that relied solely on triazoles having poorer specific weights.
The winter barley crops yielded less than usual – and also had lower specific weights – but weren’t the disaster that the wheat has been. The same can be said of the rape harvest, where yields were generally lower than recent years, but not at disastrous levels. Much of the spring barley crop remains to be cut, but it looks as if the same story will apply here.
Looking ahead to the establishment period there appears to be only one major story in this part of the world and that is SLUGS. Populations of this pest are at unprecedented levels and will require careful attention in all crops at establishment.
I would urge farmers to strictly abide by the code of practice for metaldehyde, as if we do not there is sure to be a spike of the active in water this autumn. If this occurs we will almost certainly lose metaldehyde as an approved product. This would obviously have a profound effect on our ability to control this pest in future years.