Conservation Agriculture in the UK
The following photographs show examples of the deleterious effects of over-zealous soil tillage in the UK which I observed while walking the Icknield Way, the Ridgeway, the Greensand Ridge, the John Bunyan Trail, the North Bedfordshire Heritage Trail and the Three Shires Way in southern England recently.
Ploughing and planting up and down slopes is a sure way to provoke soil erosion.
The consequences of ploughing steep slopes are evident in this picture as the uphill field headlands are starkly white and unproductive.
Soil on the up-slope side of this hedge remnant has, over the years, been retained and accumulated. Sedimentation against a hedgeline is a clear indication of erosion processes in action.
Another badly eroded headland.
Soil bereft of organic matter
An example of over-deep ploughing
Heavy machinery destroys structure and compacts the soil at depth so limiting root growth and water storage capacity.
In this picture straw bales have been split and spread over the soil as a protective and ameliorative measure.
Soil erosion from run-off in unprotected tractor wheelings
Ploughing at right angles to the contours
Black grass is a notorious weed of arable crops that can be controlled with no-till as part of CA
Beds formed after deep ploughing running up and down the slope provoke serious soil erosion. Reduced tillage, permanent beds and organic soil cover will minimize the damge
Soil with weakened structure as a result of ploughing will not withstand wheeled traffic when it is at field capacity. Essential phytosanitary operations can result in deep deformation of structureless soils. No-till and organic soil cover will help to ameliorate this situation
Hedge removal not only allows accumulated soil to be eroded, it also destroys windbreaks and, most importantly, wildlife habitat
Cultivation (with ploughs, discs or tines) compacts soils, destroys soil biota and reduces pore spaces and natural channels. Infltration rates can be cut by up to 50% and so runoff and soil erosion rapidly ensue during rain
River banks should be protected against cultivation and cattle trampling. Riparian woodland buffer zones help to dissipate stream energy, control erosion and reduce flooding whilst at the same time offering wildlife habitats
Sheet erosion on sloping soils
Sheet erosion will convert to rill erosion as runoff and slope increase
Erosion of tilled soil resulting from impeded drainage
Damage to physical works on an unprotected stream bank
Stream bank severely eroded due to the absence of vegetative cover
Severe rill erosion caused by the unprecedented rains of Jan & Feb 2014
More rill erosion from 2014
Without stream bank protection with trees, grazing animals will cause damage and provoke erosion
There are, however, hopeful signs. For example the use of agroforestry practices to combine and complement forestry, agriculture and livestock enterprises for environmental protection and biodiversity enhancement.
An agropastoral agroforestry system. Such systems are good for both species conservation, biodiversity enhancement and hillside protection
A hedge protecting a slope
A windbreak protecting fragile sandy soil in the Brecks
Oil seed rape broadcast on to wheat stubble with no tillage
A knife roller, used for bracken control but ideal for cover crop, weed and crop residue management as well!
No-till stubble will trap wind-blown snow and be a reservoir for crop growth in the following season
A Claydon (www.claydondrills.com) strip-till seed drill at work in wheat stubble
A field recently sown directly through last season's cereal residue. Eliminating tillage helps timely planting and is especially useful in 'difficult' (cold and wet) seasons
No-till field beans emerge from cereal residue. Rotating legumes and cereals is good CA practice
Although grown for game birds, this mixture of Sorghum, Phacelia, Fagopyrum and Raphanus species would be an ideal CA cover crop
No-till winter wheat survived the heavy rainfall in the UK in early 2014
Claas combine with straw spreader for subsequent direct seeding
Autocast broadcaster for OSR behind the combine header
Cambridge roll to ensure good seed-soil contact after broadcasting OSR
Spreading FYM to increase soil OM and hence enhance structure, health and fertility
Dale 8 m Ecodrill direct drilling in stubble with crop residues and FYM applied to the surface
These issues are being debated in the agricultural development community. Here are some of my contributions to the debate that have been published in Landwards, the professional journal of the Institution of Agricultural Engineers in the UK.
Letter to the Editor: Landwards Vol 64 No 1 Spring 2009 page 9
Letter to the Editor: Landwards Vol 66 No 2 Summer 2011 page 10
Article in Landwards Vol 66 No 3 Autumn 2011 page 21
Sustainable land management in Britain: Landwards Vol 68 No 2 Summer 2013 p24
Groundswell No-till Show, 2016: Landwards Vol 71 No 3 Autumn 2016 p5
Groundswell No-Till Show: full report
Other useful links are:
An account of a recent visit to Tony Reynolds' no-till farm in Lincolnshire organised by the Tropical Agriculture Association
A decade of CA at Thurlby Grange Farm, Bourne, Lincolnshire. From the TAA website
Visit to Tony Reynolds at Thurlby Grange Farm: No-till farming in the Lincolnshire fens
No time to till - British Farmer and Grower, April 2017