Worcestershire farmer Jim Bullock reports from the European Conservation Agriculture Federation’s German farm-based no-till meeting.
Leipzig, where the European Conservation Agriculture Federation held its no-till farm discussions, is well known for its silty-sand soils and undulating landscapes.
Rainfall in the former East Germany is low – 600mm a year – but much falls in heavy storms in spring and autumn, when there is bare soil pre-drilling. The result, when combined with large fields of over 400ha, can be serious soil erosion.
The local advisory service has been promoting min-till and mulch tillage as a means of reducing run-off, but it has had limited success. The view now is that conservation agriculture (no-till) is the way forward.
It was against that background that I, with 14 other delegates from eight European countries, visited Thomas Sander’s farm in the region. He grows 430ha of combinable crops – as much wheat as possible, with oats, barley, peas, beans or maize “in between crops”.
Mr Sander started conservation tillage eight years ago using a triple-disc drill, but after limited success, he bought a New Zealand-built Cross Slot drill in 2004 (thumbnail image). At the same time he implemented the principles of conservation agriculture on the farm.
So, along with minimal soil disturbance for crop establishment and a diverse crop rotation, he now tries to ensure he has total soil cover all year round, with a growing cash crop, crop residues or a cover crop.
Cover crops are increasingly important to him to improve soil structure and fertility. The soil should always be growing something, otherwise the flora and fauna have nothing to feed on and the soil becomes dead, he says.
Mr Sander’s first challenge, as with all no-tillers, was effectively dealing with crop residues. Although his Claas Lexion 460 combine could chop and redistribute cereal straw effectively enough for systems involving some tillage, in a no-till situation he found it was better to leave the stubble as long as possible so it remains evenly distributed.
He now uses a Shelbourne Reynolds stripper header, which not only increases combine output, but leaves the entire cereal crop residue standing so it remains open and dries out even after heavy rain. Equally important, it provides soil cover and breaks down over a much longer period, not tying up soil N when the next crop is establishing.
One unexpected downside to the technique has been an explosion is the local mouse population. It provides excellent predator cover, and mice have thrived, consuming seeds of crops such as peas, beans, maize and oilseed rape. Baiting is one option cultural techniques and encouraging predators are another.
Where the stripper header is not used, a straw-harrow (pictured)/Cambridge roll combination re-distributes crop residues and crushes slugs and their habitats as soon as possible after harvest. The operation is repeated 10-14 days later.
Oilseed rape stalks create an ideal slug residence, so Mr Sander often shreds it with a PTO-driven flail mower operating at a low flail rpm but high forward speed. This breaks up the stalks and exposes the slug and its eggs to the elements.
Cover crops are established if there is going to be more than six weeks between crops, and the previous crop is unlikely to provide soil cover with volunteers. What the cover crop is depends on the next cash crop. For example, between winter cereals mustard or possibly some vetches might be broadcast into the previous cereal, but where a more high-value spring crop, such as grain maize, is to be grown, a more complex mixture may be drilled with the cross-slot.
All main crops are drilled using the cross-slot. Although it appears heavy and large for a 3m working width, it can drill 20ha a day, according to Mr Sanders. He runs drill and tractor on low ground pressure tyres, which can have the pressure adjusted on the move (picture below), to reduce soil compaction.
Mr Sanders is advised by no-till agronomist and soil specialist, York Bayer. He has spent a number of years developing no-till systems specific to European conditions. His evidence suggests crop yields can equal and even exceed those of conventional farmers in the area, with much reduced inputs.
Mr Bayer is a firm believer in disc drills – he imports Cross Slots into Germany. He has reservations about tine drills because no-till requires as much surface residue as possible. And he gets over the problem of hair pinning with disc drills by advising growers to drill into a living cover crop or volunteers before being sprayed off post-drilling.
Living crops are easier to cut with a disc, he explains, while any residue or cover crop that is hair pinned into the slot is not covered in glyphosate, which can inhibit germination. He also claims that having living material on the surface means slugs remain on the surface too, making them easier to control with surface-applied bait.
Weed control is another potential no-till problem. But the Germans’ showed that as long as you have soil cover and minimal establishment disturbance, many weed seeds fail to germinate or are sufficiently weak to be smothered by the growing crop.
Mr Bayer demonstrated wheat crops that had received a post-drilling glyphosate and spring broadleaved weed application. And, yes, grassweeds are a problem on German farms. But these crops, although not weed-free, were no worse than surrounding crops with a more conventional herbicide programme.
But to achieve adequate weed control with so few herbicides requires a different approach to crop nutrition, he says. Fewer weeds grow when fertiliser is placed, so he advises any autumn fertiliser is placed at drilling. In the early years of conversion, it pays to apply 30kg/ha N to give cereal crops a boost and help them develop a strong root system.
This 12m monster is a controlled uptake long-term ammonium nutrition (CULTAN) liquid fertiliser applicator. Ammonium sulphate is injected into the soil and is slowly released during the growing season as the crop requires it. York Bayer’s no-till clients typically apply 20-30kg/ha N at drilling, and then 140kg/ha N around GS31. Growers using it have found they need no growth regulators or fungicides and still achieve yields of 8t/ha.
No-till guru’s 10 point plan
International no-till consultant Rolph Derpsch believes there is no reason why no-till shouldn’t work on 80-90% of soils in the UK, as long they don’t become waterlogged.
Jim Bullock’s visit conclusions (or why UK no-till hasn’t taken off)
- Most growers trying no-till are guilty of substituting the plough with a no-till drill it has not been looked at as a system
- We are too quick to revert to cultivation when, in many cases, it is poor drill design and operation that is at fault
- No adjustments have been made to nutrition programmes, despite the availability and distribution of soil nutrients changes with no-till. Few UK-available drills are able to place fertiliser at drilling times, which may be essential in some circumstances
- Our crop rotations may not be diverse enough to break pest, weed and disease cycles, although they might be profitable in the short-term
- Successful UK direct drills tend to move a lot of soil, which mineralises N and improves crop establishment, but this leads to a weed control problem. A minimum disturbance drill capable of fertiliser placement might be the answer.
- Many soils are low in organic matter and suffer from poor structure due to excessive cultivations and wheelings. This makes them unsuitable for no-till in their present state
- We need to look at crop residue management in greater detail. In a min-till system a fine chop of straw and stubble is necessary for effective operation of cultivation machinery, but not in no-till. Thick mats of chopped straw on the soil surface are a complete disaster (slugs, wet soils, etc.)
- Some UK farms are short of labour at critical times and so are unwilling to establish and managing cover crops
- Ill-thought out no-till trials and demonstrations have put off a lot of potential growers
- Many agronomists and researchers have little knowledge of no-till and are not prepared to take the system on board
Reasons why no-till could take off in UK
- New drill developments
- Input cost-inflation and environmental pressures encouraging growers
- Innovative growers designing successful systems