The temptation to get winter wheat sown early this autumn will be very hard to resist, even where there’s a known black-grass issue.
Yet we know the chances of a repeat of last year’s weather are very slim. We also know how effectively delayed drilling reduces black-grass populations. So why are we tempted to abandon reason and get those crops in the ground?
It’s a question we sought to answer with the help of Dr Karen Barton, a chartered clinical psychologist.
“It’s effectively an anxiety response,” she explains.
“Conditions last autumn threatened livelihoods and the resulting anxiety is both entirely natural and normal. Fundamentally, the weather last year triggered a fight or flight response,” she says.
“Humans have evolved an acute reaction to threats. Historically, people that were highly reactive to sightings of predators, for example, were much more likely to survive than those who were more relaxed. Over time we’ve been selected to have a highly tuned ‘better safe than sorry’ attitude.”
“Any situations involving both a threat and decision-making, engages two areas of the brain, the amygdala and the frontal cortex.”
“The amygdala processes anxiety, while the frontal cortex is responsible for logic and decision-making,” Dr Barton continues.
“The amygdala communicates with the rest of the body through the sympathetic nervous system which ultimately produces adrenaline. It’s like a super highway; once a chemical response is triggered by a perceived threat, the body is ready for fight or flight. It’s a highly effective mechanism for the situations we have evolved with but it’s not always so useful in dealing with the situations we face today.”
“The mechanism by which frontal cortex communicates with the body, is much slower which is why, when the amygdala is engaged and adrenaline is high, logic and reason don’t have an impact. It’s action that relieves and calms the sympathetic nervous system.”
After seeing long-range forecasts, growers may well be advised to wait until adrenaline levels have dropped to enable a more balanced decision regarding drilling dates. For some this may mean going for a run, others may prefer to speak to a trusted advisor.
Our agronomy manager, Andrew Clune, agrees. “Last year was horrendous and now, with crops already harvested, and good levels of moisture there’s the potential for some good seedbeds,” he acknowledges.
“But not every year is like last year, and we normally get windows of opportunity to drill somewhere later in the season.”
“The impact of delayed drilling on black-grass is well documented and I’d strongly advise growers to put off sowing wheat until mid-October where there is a black-grass problem.”
“For those that don’t, bear in mind that the crop will be in the ground growing for a month longer than it normally would. And it’s a month in which we know black-grass will germinate. Growers will have to manage that, starting with a robust pre-em like Crystal®.”
“Activity from a fluenacet-based pre-em will last around 40 days,” he says. “It will be running out of steam at a time when black-grass is still germinating and that means growers will need to follow-up with a post-em.”
“There’s another complication. We’re in a high dormancy year and we don’t yet know when the blackgrass will break dormancy and germinate,” adds Mr Clune.
Like many other growers across the country, Richard Hinchliffe from South Yorkshire felt the effects of the weather in autumn 2019. “Last year threw us all out. It started raining 23rd September, the day I was due to start drilling, and didn’t stop.”
“We had a couple of dry days in October when I got a field or two drilled but otherwise it didn’t stop raining again until November. I had 185mm of rain in October,” he recalls.
Mr Hinchliffe has been delaying drilling on his 1,400 acre family farm for six years.
“It’s a needs must,” he says. “When you have a bad black-grass situation it has to be the driver behind all your decisions.”
10 years ago Mr Hinchliffe would have drilled his entire acreage by the start of October. Today, he won’t start drilling until the 20th September, even in clean fields.
“Research shows that, on average, each week drilling is delayed from mid-September to mid-October, there’s an additional 15% control. After mid-October control drops to 5% per week.”
“There’s is a tipping point though,” acknowledges Mr Hinchliffe. If you delay too long and end up with a thin poor crop, the black-grass will take advantage of the lack of competition.”
“Like all things farming, it’s a balancing act. Balancing the loss of yield and profitability from black-grass with the loss of yield from a later start.”