One thing is clear, given the amount of consideration to soil types and cropping, in the end it becomes a very personal decision. Mike Abram looks at why four grow have chosen their systems.
The cultivation systems growers use to establish crops, or indeed whether to cultivate at all, have created many hours of discussion in pubs, forums and on social media channels over the past 20 years.
Part of the reason it creates so much debate is there are so many factors to consider, from climate to weed control requirements, the area to establish in what time frame, to reliability and cost.
That varies so much from farm to farm and soil type to soil type, so it is no wonder there are so many different opinions about which system is the best to use.
Countering that requires flexibility, suggests Ed Worts, arable product specialist with machinery manufacturer Kuhn.
That can either be in what kit is available on-farm, or by how equipment can be set up.
“There is equipment that can be used at multiple depths and situations, such as working at deeper cultivation depths when you’re trying to alleviate compaction, and to a much shallower depth when that is all that is required.
“Or drills like the Kuhn Aurock which has a full width packer option and means it can be used in min-till and direct drilling situations when making that transition.” One important factor when considering new equipment purchases is how easy is it to change settings, he says.
“If it is easy to adjust then farmers are much more likely to take that extra time to set the machine up correctly.” For very shallow cultivations it is critical for the set-up to be parallel to the ground from front to back and side to side, he adds.
“At shallow working depth, if one side lifts by 20mm, you can potentially halve your working depth, whereas with deeper cultivations it is not as critical.
“We’ve now developed 12-metre wide disc cultivators and we’re working on active ground following systems to ensure the machines are working at the same depth across the larger working widths.” Ploughs also offer flexibility, not so much in purpose, but in being able to help provide an almost weather-proof establishment system, he says.
Plough sales are relatively stable, with a shift towards on-land ploughs because of easier use with GPS systems and reduced compaction, despite their relatively high cost in wearing metal, fuel use and time.
However, there has been a trend away from deeper cultivation min-till kit, partly for those reasons, says Mr Worts.
“I think farmers have realised they don’t need to be working that deep for a lot of their crops.” Weed control is also driving some of that trend, according to Craig Simpson, commercial technical manager for Bayer.
He says: “There is no one-size-fits-all policy that fits cultivation and weed control.
“Knowledge of weed population dynamics in terms of firstly correctly identifying problem weed species and understanding how many and where they are in the soil profile is crucial to help using the right cultivation approach to minimise the number of weeds you’re trying to control in the crop.”
That’s leading to two popular approaches, especially on black-grass land – either burying seeds at depth with the plough or using shallow cultivations to deal with a minimised weed seed bank from the previous crop.
To give perspective on how all those challenges make cultivation decision-making so varied, Arable Farming approached four farmers to talk through their situations across four very different land types.
Flexibility is fundamental to the success of Colin Chappell’s crop establishment policy.
He has little other choice thanks to high magnesium content clay soils on the banks of River Ancholme, Brigg, which, because of magnesium’s greater attraction for water, do not take much to get sticky and difficult to work.
That is made worse by repeated flooding, partly because the river levels are controlled by the Environment Agency, as well as seemingly more frequent heavy rain events.
And when the soils do dry out, they tend to shrink which brings its own problems, opening slots and exposing seed.
Ideally, he would like to do as little cultivation as possible, but previous attempts at no-till establishment made him recognise that his soils were not ready for it.
“The plan is over seven or eight years you make the soil easier to work, more amenable to whatever kit you want.” That plan includes starting to maintain cover as much as possible through the year and he has seen improvements in water infiltration rates.
“We are finding less puddling, but also less droughting as water passes through the soil profile quicker, while retaining more water for the roots to access.
But I know I haven’t perfected using cover crops yet.” For now, he has become an opportunistic direct driller when conditions allow – typically winter wheat after peas or beans.
“Usually I have to do a form of cultivation in front of the drill, which currently is with a low disturbance sub-soiler following the combine.
If it is going to be bare over winter or a long period of time I sow a cover crop off the back of it.
“And then I follow up eight times out of 10 with a disc cultivator drill.
That works the soil just enough, tickling the surface to provide a bit of mineralisation to allow the drill to do its job.
“In wet conditions, usually between November and February, we tend to switch to a tine drill, which works better in those conditions.
It also works well on another part of the farm where the soil is limestone brash and can be a one-pass system.” With black-grass a major challenge, the farm’s spring cropping area has increased.
Again, ideally he destroys the cover crop and drills without any further cultivation.
“But because the soil isn’t in good enough heart yet, it sometime slumps, so then I use the tine drill as a cultivator ahead of the disc cultivator drill, which with the cultivator kit on the front gives that little bit of fine crumb to get it away before it gets droughted.” A key part of his black-grass control strategy is to spring crop three years in a row on his heavy land.
“Multiple years of spring cropping to then get your ultimate first wheat without needing to use too much chemistry to grow it.” Cultivations are then used t o make sure he does not undo that good work as far as possible.
“I’ve found less is more when it comes to black-grass.”
Reliability of establishment is crucial for Stewart Cavers, who farms 760 hectares at Crosshall, Greenlaw, in the Scottish Borders.
With medium loam soils capable of averaging more than 10 tonnes per hectare of winter wheat, 5t/ha of oilseed rape and 8t/ha spring barley, but usually only one chance to put a crop in, reliability in his cultivation practices is high on his list of requirements.
Up until the turn of the century, that meant ploughing every field every year, but the advantages of using a deeper semi-inversion tillage system based on a disc/tine cultivator quickly became apparent.
“It gives a firmer seedbed, a better tilth, keeps the moisture in, all in one pass before drilling with a six-metre combination drill,” explains Mr Cavers.
It also allows him to cover ground faster with reduced fuel usage and he’s seen improved slug control, particularly in oilseed rape.
“We’re finding we’re starting to min-till ahead of some spring crops more as well.
For example, it is a long time between ploughing in October or November to drilling vining peas in May or June and with Scottish winter rainfall, you risk erosion and losing a lot of nutrients and organic matter.
“It doesn’t feel right to be leaving the soil bare that long, so anything going into peas we’re putting a cover crop of black oats and phacelia in, which is really helping improve organic matter and ticks the carbon footprint box.
“We also run sheep so we get some winter grazing after January.
Yields of the peas last year where we cover cropped were noticeably better than in a field we ploughed and left.” But the plough is far from being consigned to the weeds, being used ahead of both winter and spring barley crops.
It both helps from spreading the workload, especially ahead of spring drilling and for weed management.
“I think it’s important to have a clean canvas ahead of barley.” Sterile brome is becoming more of an issue in places on-farm, so the plough helps keep that under control, he says.
It’s also a good fallback tool for when conditions change, such as later in autumn when it starts getting a bit sticky for the disc/tine cultivator.
“I wouldn’t want to be without it.
On our ground you can plough and put a combination drill on top and know you’ll get a decent crop.” He uses a semi-mounted seven-furrow Kuhn Vari-Leader, with slatted bodies.
“We went for those because they break the ground up a little better to give a bit more tilth than a mouldboard.” The combination of plough and semi-inversion gives him the best flexibility to meet his aims of guaranteed good establishment, he says.
And with traffic across fields high with straw removed and cattle muck spread, he can’t see a time when shallower tillage will be employed.
“I think you’re better going a little bit deeper,” he adds.
Cost cutting was the initial driver for Chris Marchment to ditch the plough nearly 15 years ago on his 80-hectare farm at Andover, Hampshire.
His challenge is working clay-capped soils over chalk with one block having considerable flints and the costs of wearing metal and diesel had made ploughing an expensive establishment method.
The flint content of his soils also put him off direct drilling anything other than his winter beans.
He’s also keen to make sure there’s good seed-to-soil contact, so he employs a reduced tillage system where he cultivates no more than the top 10cm of soil using a Kuhn Cultimer.
“It’s like it was almost built for me,” he says.
“It has transformed my cultivations.” The Cultimer has three rows of staggered tines, a row of levelling discs and a rear roller.
Mr Marchment uses front depth control wheels and wings on the tines to work the soil to 10cm depth.
He employs the Cultimer as soon as possible after harvest.
“It moves and mixes the chopped straw and stubble so well that most of the residue has disappeared when you get to drilling.”
Tungsten-tipped points on the tines and the double spring loaded non-stop mechanical break-back system are particularly useful features on his flint soils, as is its ease of set up and adjustment.
He has found the lower disturbance method has also helped with his weed control.
“It’s been a knock-on effect that it has been easier to control weeds.
Effectively, it creates a stale seedbed, which we can let green up and then spray off before drilling.” Not having to struggle with black-grass, he aims to have winter wheat drilled by the first week of October.
The move to a shallower tillage regime has seen improvements in his soils, he says, helped by starting to use mustard as a cover crop.
“The ground works 100% easier than it did when we were ploughing.
Less is more,” he adds.
A commitment to a regenerative agriculture approach to farming with direct drilling as an important plank has helped Clive Bailye, growing combinable crops at scale near Lichfield, Staffordshire, halve his fixed cost structure since switching from a min-till approach in 2006.
He has a two-pronged approach to direct drilling on soils, which range from Wick series medium loams and sands over gravel on the home farm to soils with higher clay content on some of the contract land he also farms.
The bulk of the work is done by a 12-metre disc drill, which copes well with drilling direct into cover crops as well as having a high output.
But in wetter conditions – as the past two autumns have been to some degree – he also uses a farm-workshop-modified 6m tine drill in combination with a front hopper.
“In the last two years we have used that much more than we would usually plan to.” Wet soils can make direct drilling challenging, he says.
“Even on our lighter soils it can be difficult to get the slot to close.
The basics are important with no-till just like with any farming system – correct drainage is more important than the brand of drill.” With a lower fixed cost structure, plan B of spring cropping is much more palatable, he adds.
“The whole point of our system is that using less machinery, horsepower, fuel and labour means I don’t need the high outputs to maintain profitability.”
The change of approach has helped get on top of grassweed challenges, particularly sterile brome, that had been increasing under a previous deeper non-inversion approach, using a set of disc harrows and disc cultivator drill.
“No-till is not a silver bullet for grass-weeds.
It helps because you’re keeping the problem on the surface where it is easier to treat rather than mixing it in the soil profile.
“But the thing that made the biggest difference in our system was the shift in rotation to more spring cropping, including later sown spring crops such as linseed and millet, which give any surface germinating grassweeds, such as brome, plenty of opportunity to germinate and be taken out by a glyphosate application.
“Having more crops in the rotation also means we’re using more modes of action – we’re not heavily relying on one or two groups of actives and a healthy rotation of actives should help avoid some of the resistance problems that can happen,” he says.