In a quest to achieve long-term sustainability, deploying a range of techniques – from precision farming to using adjuvants – is proving to be
key for one Lincolnshire grower.
Over the past 13 years, Peter Cartwright has taken the arable enterprise at the Revesby Estate in Lincolnshire from a heavily tilled operation to one that is now almost exclusively based on direct drilling – as well as dramatically changing the rotation, with the aim of improving the overall sustainability of the business.
And he’s not stopping there. Having already cut insecticides from the wheat and bean crops, Peter is working with his long-standing agronomist, Richard Butler of Agrii, to seek further efficiencies. Starting with the rotation, knowing milling specification is difficult to achieve without high quantities of nitrogen, wheat is now grown mostly for feed. “Nitrogen is the biggest carbon input on the farm, so I’m keen
to reduce it,” says Peter. “Yields are heading towards 10t/ha with our feed wheat – so we’re producing a good ‘barn-filler’ without the need
for much nitrogen.”
He adds that they have also put N-sensors in the ground to better understand what nitrogen is available and therefore help them to make better decisions about applications. The rest of the rotation, which spans across 1,200ha, comprises spring barley, oilseed rape, winter and spring beans, spring oats, sugar beet and cover crops. “Beans are grown for seed and the oats for milling,” explains Peter. “We also do a bit
of malting barley after late-lifted sugar beet.
“Beet is a useful break crop for us, and it’s only grown on land that suits it. It also yields well – we achieved 74 t/ha in 2023.” In terms of establishment, 95% of crops are established via direct drilling, having transitioned away from a traditional ploughbased system. As well as the cost and carbon-saving benefits this has brought, Peter says it’s also advantageous for the soils, creating a more resilient structure which
improves crop production.
The change in establishment techniques has proved beneficial in reducing the black-grass problem on farm too. “Being flat land, below sea level, we’ve been heavily burdened by black-grass,” explains Peter. “However, by employing cultural controls and optimising the performance of chemistry, the once hay-like fields have been brought back to manageable levels.”
Keen to achieve the highest level of control possible, the Revesby Estate is the host farm for Agrii’s mid-Lincolnshire Technology Centre
– a decision driven by Peter’s keen interest in trials and desire to understand what’s working and delivering value and what isn’t.
Working with Richard, Peter has based his approach around five key steps. “No disturbance direct drilling has been the first step, followed by trials with varieties rated for their black-grass control, to help select the most vigorous options,” he explains. “We then looked at seed rates and found 450 seeds/sqm to be optimal. We did try as high as 750 seeds in spring wheat and while, yes it outcompeted the black-grass, the cost of the seed was too high.”
At the other end of the spectrum, Peter says that at 250 seeds/sqm the black-grass was “horrendous”. The fourth step of the plan involved altering drilling date. “We opted to delay the drilling of winter crops until mid-October. Now, we let the flush of black-grass come through and then spray it all off to keep weed levels to a minimum.”
The final part of the approach is herbicide choice, which includes optimising performance with an adjuvant, to help Peter
achieve near to 100% control.
“As a base, we apply Liberator (flufenacet + diflufenican) and Bandur (aclonifen) at pre-emergence and top up the flufenacet
peri-emergence,” explains Peter. “The next step up is to use Luxinum Plus (cinmethylin) and Pontos (flufenacet + picolinafen), but with
everything we include Backrow Max in the mix to optimise the application itself and the performance of the application.
“It also gives valuable drift reduction which extends the spray window, particularly during catchy weather. Holding the herbicide longer
in the weed germination zone is also a key driver for using Backrow Max, and combined, this all helps us deliver on those crucial percentage gains.”
“It also gives valuable drift reduction which extends the spray window, particularly during catchy weather. Holding the herbicide longer in the weed germination zone is also a key driver for using Backrow Max, and combined, this all helps us deliver on those crucial percentage gains.”
Backrow Max is a specialist residual herbicide adjuvant that can be applied with pre- and peri-emergence tank mixes to maximise performance in all weather conditions. It does this by optimising herbicide droplet size and binding to clay particles in the soil, meaning that both coverage and longevity is maximised.
The drift-reducing benefits delivered by Backrow Max came into their own this autumn with Storm Babet, notes Peter. “It was a season of relentless rain and catchy weather, making it more important than ever to keep on top of the black-grass and ensure herbicides kept working in the weed zone for as long as possible.”
Looking to the future, nothing is set in stone and Peter says he isn’t one to make sudden changes. “Everything is about trialling, measuring, refining and even going back to the drawing board if needed.”
One thing he is planning to do next year, however, is to use Rhiza to help look at the long-term plan to reduce inputs – mainly nutrition and crop protection. “I really want to tear up the rule book on T1 and T2 and I’m going to use Rhiza to help plan treatments based on when disease is likely to come in,” says Peter. “The hope is that we may be able to treat once and then top up the potency with an adjuvant like Kantor, for example.
“I also want to investigate the trace element side of things with adjuvants and see if they can help optimise adhesion and uptake. At the moment, we apply magnesium and manganese every time we go through the crop in season as have low magnesium soils, so I’m keen to see what else we can do.”