RAPID TRASH FLOW: The improved residue flow from the design of its latest drill enables a Cotswold Estate to sow in wetter, trashier soil conditions.
One high horsepower tractor, a bigger drill of a different make and operating principle, and a wider cultivator. These were the results of a major change in the machinery policy six years ago at Cirencester Park Farms Ltd’s Ewe Pens Farm, a part of the Bathurst Estate.
“There had been a big increase in the arable land farmed, we’d taken on another 300ha and needed the power and the width of implements that would enable us to increase output to improve timeliness and reduce costs, and handle any further expansion, which there has been,” explains farms manager, Stuart Batchelor.
His challenge is maximising output from the region’s free-draining Cotswold brash over limestone, which can vary in depth from 15cm to 45cm on some of the ‘better’ ground.
“Our objective is to get as much as we can from our limited soil resources and make them more resilient to spring drought, they are easy working but if we don’t get rain in April and May yields can be disastrous,” Mr Batchelor explains. “Due to our altitude – 750ft above sea level, so we’re colder and later in the spring – and the thinness of the soil good establishment is essential, we need to get a well-established crop and get the roots down.
“Our target is to get the oilseed rape in by the end of August and the wheat during the first fortnight in October; I believe in the maxim that ‘a seed well sown is half grown’ and provide competition against blackgrass and other weeds.
“We are extremely conscious of the need to increase organic matter and only bale straw in front of oilseed rape, the rest is chopped off the back of the combine and incorporated. And we import a lot of sewage sludge, FYM and digestate, which has also enabled us to reduce our use of Triple Super Phospate.”
The effectiveness of those measures is reflected in “better than anticipated” 2017 oilseed rape and winter wheat yields of 4.3t/ha and 8.8t/ha, respectively, despite of 10ml of rain in April then none until mid-May.
The paucity of soil depth has also been the primary factor in changes in cropping. Historically Cirencester Park Farms Ltd’s land was in a typical Cotswold rotation: winter wheat, winter barley, oilseed rape. But for the past four years the arable ground, currently 1832ha, has been farmed in three rotations. Growing conserved fodder for a neighbouring dairy farm influences one programme, the land down to a winter wheat, maize (141ha), winter wheat, oilseed rape cycle.
On the deeper brash spring beans replace the maize, on the thinner soils winter wheat is followed by two barley crops (either winter or spring barley) before oilseed rape. All wheat (704ha for the 2018 harvest) are feed varieties, as is the 45ha of winter barley. Spring barley (260ha conventional and 41ha organic) is for malting. Oilseed rape and spring beans account for 474 and 119ha, respectfully. There are also 47ha of arable fallow and 437ha of grass and ELS/HLS.
“We grow oilseed rape one in four years as, although it has a high gross margin, I think growing it too often is a short term view as there are the potential problems of black grass and slugs,” says Mr Batchelor. “The spring crops help us to keep on top of black grass but on the worst fields we are also meeting points requirements for the basic payment scheme using fallow and trialling a 2 – 4-year herbal ley (grasses/clovers/sainfoin) in these fields.”
A variety of techniques are used to prepare the land for sowing. Oilseed rape is sown direct into stubble with a Vaderstad TopDown cultivator/BioDrill combination. Winter wheat land is cultivated and, if needed to create a suitable seedbed and “knock slugs about”, a pass with a 6m Vaderstad NZA spring tine.
The spring bean land and, when possible, all the winter barley ground is ploughed with an 8-furrow Lemken on-land reversible then spring tined. Fields destined for spring barley are either cultivated or ploughed (every four years) then over-wintered. Post-drilling consolidation is with one or two passes with a 16m set of Cousins rolls with breaker rings.
“We try and do the majority of spring crop ploughing in September,” Mr Batchelor says. “Some over-wintered stubbles are cultivated in February/March.” On the maize land FYM is ploughed in with a 6-furrow Kuhn before a pass with a 6m Vaderstad Rexius Twin and drilling by a contractor.
Until 2012 the primary workload was carried out with a 300hp wheeled MF8670 and a 350hp MF8690 hired in from mid-August to mid-September to enable the heavy cultivations and the oilseed rape establishment to be done at the same time.
The restructuring of the machinery fleet brought about by the additional land saw an end to the hiring-in policy. It also involved trading in the MF8670 against a 320hp Challenger MT765C to do all the primary cultivations and sowing with a wider, 5m TopDown and a bigger drill of a different make and type: an 8m Vaderstad Rapid fitted with System Aggressive discs.
“I’d had experience of the Rapid and I think the depth control and the layout of the working elements, two rows of cultivations discs, a levelling board and two banks of drilling coulters, maintains the seed depth better than tines, which can have a lot of movement, and produces more uniform establishment,” Mr Batchelor says. “Also, the discs have the whole weight of the drill on top of them. We drill at 10 – 16kph, depending on the stone content.”
But the Rapid was not faultless. “In really wet conditions it blocked up between the two rows of coulter discs,” Mr Batchelor says. That issue was addressed at the beginning of last year when the drill was replaced with another 8m Rapid, specified with the optional tool layout of two rows of System Aggressive cultivating discs and a third bank of coulter discs in place of the levelling board.
“It still drills at 12cm as there are the same number of discs but as they are spread out more there is greater room for trash flow,” he says. “It coped with long maize stubble, although we did manage to block it drilling beans on a wet headland by a wood: everything has its limits!”
The drill is also fitted with the E-Services System, which is used for variable rate seeding, rather than variable rate fertiliser, to compensate for variations in soil type and depth. “Courtyard Agriculture has scanned and zoned all the arable fields into different soil types and zones are sampled every three years,” says Mr Batchelor. “Wheat and barley seed rates vary between 300 – 450 seeds/m2.”
Although Cirencester Park Farms Ltd has used the modified Rapid for only one autumn Mr Batchelor believes the investment has been worth it. “We drilled wheat in November with no problems and (at the end of February) establishment looks reasonable,” he says. “It’s too early to comment on yield but the potential is similar to the previous drill as the principle is the same but with the flexibility to cope with wetter, trashier conditions.”