Between June 1 and July 16 we had just 9.6mm of rain. However, as I write this on July 17, I can report that the heavens finally opened.
With overnight thundershowers bringing 20mm of rain to parched fields here in the North East, once again farming proves itself to be a process of managing crops for extreme weathers.
Combines have just started to roll into the winter barley and, so far, results seem better than feared both in terms of yield and quality. Let’s hope this trend follows into the wheat, which started to senesce early in the late June/July heat. Spring cereals have coped incredibly well considering the late drilling date and continued dry conditions, but are unlikely to break records. Spring beans have podded well and hopefully the recent rain will help them fill. By contrast, winter beans started to show drought stress about 10 days ago and may struggle.
As stubbles are cleared thoughts move towards oilseed rape drilling. The growing of OSR has become more of a challenge in recent years, exacerbated by the neonicotinoid seed treatment ban. I do accept that the crop has its challenges but it is still the top gross margin break crop option on most farms in the region in which I walk crops. It also provides a very valuable grass weed break, especially where rye-grass persists. Notable black-grass control can be achieved with careful management too.
There are many methods of establishment but my view is that OSR always does best when sown with a leg under the seed. Fine and firm seedbeds aid rapid and even establishment, as well as help in the battle against flea beetle. In terms of drilling date, I’m not a fan of doing it ‘ultra early’ which seems to be in vogue.
Crops sown early August tend to suffer more with clubroot and foliar diseases, get too advanced ahead of winter and rarely deliver top yields. The second half of August onwards, into moisture, is where I think we should aim.
Most of my growers now apply seedbed fertiliser in the form of DAP or liquid N and P, much of which is placed in the drill seam. This boost to early crop growth is another way to offset flea beetle. It is worth checking soil pH before sowing OSR and, increasingly, we are suggesting maintaining a pH of 7+ to ward off clubroot. Where we can access it, Limex seems to work well ahead of OSR.
In instances where we are confident of good establishment, a pre-em herbicide is still the norm here in the North. The key target species are shepherd’s purse, cranesbill, cleaver, hedge mustard and mayweed. Clomazone is a useful product for controlling shepherd’s purse, hedge mustard and chickweed and still gives reasonable control in dry conditions.
It is understandable that we are all interested in it, but yield is only one factor to consider in OSR variety selection. For us in the North is light leaf spot resistance, vigour, standing ability and pod shatter resistance are equally important. On farms where Centurion Max [clethodim] is to be used, I think variety selection needs to be very carefully considered. In my view, some varieties are much more sensitive to Centurion Max than others and with this in mind, take advice before selecting varieties if you are unsure.
At the moment, we are seeing a growing interest in Clearfield rape varieties, fuelled initially by increasing issues with brassica weeds but, more recently, problems with erucic acid contamination too. Field performance of these varieties is improving all the time, making this a credible option for many growers now. However, the concept does need a bit of forward planning, as Imazamox-based herbicides will not cover all the broadleaved weeds. In many cases, a pre- or early post-em spray will be needed to augment the Imazamox mixture.
There is much to weigh up and invest to ensure a good rape crop, but get it right and the benefits can make it all worthwhile.