Late drilling clue to harvest survey results
Farmers have seen greater variability in winter wheat yields over the past decade than they did in the previous five years.
We track crop performance through our annual harvest survey, and have identified that while average winter wheat yields have slowly climbed since our survey began 19 years ago, growers are now seeing a wider range in yields from year to year.
According to George Badger, farming consultant and agronomist in the Cambridge office: “Up until 2008 you can see that yields were relatively consistent year on year, but afterwards the variability seems to be a lot higher.
“While the low of 2012 and the highs of 2014 and 2015 are a lot to do with the fortunes of rainfall and sunshine, we think there is another factor at play.
“Our survey data, which this year covers 58,000ha, is largely gathered from farms in the East of England and the Midlands where blackgrass is an issue. It is our belief that part of the explanation is a shift to later drilling, as part of a strategy to tackle blackgrass once resistance to contact post-emergence herbicides became more evident from 2010 onwards.
“Late drilling is an essential grass weed management tool, but it does result in smaller root structures which leave crops more vulnerable to weather extremes than they were when people could reliably drill in September.”
Mr Badger stressed that delayed drilling - after October 15 - remained the right course of action on the worst-affected fields, as it gave growers the best chance of both cultural and chemical weed control.
According to provisional results of the survey, the most significant change in crop performance was seen in winter oilseed rape yields which rose 27 per cent, from a disappointing 2.9t/ha in 2016 to 3.7t/ha in 2017.
The overall winter wheat yield for 2017 was 9.1t/ha, which was up two per cent on the previous year’s average of 8.9t/ha.
The increase was largely attributable to the better performance of first wheats which yielded an average of nearly 9.5t/ha, compared to 9.2t/ha in 2016. In contrast, second wheats came under more pressure and averaged 7.8t/ha, compared to nearly 8.8t/ha last year.
Reflecting the challenging year for spring crops, because of the lack of rainfall in April, spring barley yields were down seven per cent on last year’s levels to just under 6.0t/ha. Lodging was an issue in a number of crops, as was brackling, which led to high harvest losses as not all the crop could be picked up.
Spring beans also struggled in the dry conditions with yields averaging 3.8t/ha.
There was better news for growers of winter barley, who saw yields rise nine per cent to average 7.3t/ha.
James Turner, farming consultant, Strutt & Parker
