A new model for organic 'shhep and corn' farming on the Brighton Downs
A new model for organic 'sheep and corn' farming
on the Brighton Downs?
Dave Bangs, Brighton Downs Alliance co-founder, March 2021,
T: 01273 620 815
My note is dependent upon - and quotes extensively from - the excellent article by John Letts entitled 'Continuous Grain Cropping' in 'The Land' magazine, Issue 27, 2020, pages 28-34. This article is drawn from a longer paper 'Continuous Grain Cropping CGC: How to Grow Grain while Increasing Biodiversity and Sequestrating Carbon', 15th March 2020, awaiting publication.
Brighton tenant farmers don't sign up for organic production
Despite all the major Brighton Downland Estate farm tenancies being signed up to stewardship agri-environmental agreements, only one farm is signed up for the Organic Level Stewardship prescriptions, that of David Robinson of Northease Farm, who rents pasture land at and near Stanmer Park.
Given the current farm economies of most of the major Brighton Estate tenants that limited take-up of the organic option is not a surprise.
Most of them are mixed enterprises of grazing and arable, and the arable components are very large, conventional and intensive: - as at Mile Oak, Paythorne, Standean, Stanmer Home Farm, High Park, Balmer, Housedean, Upper Bevendean, Balsdean, Ovingdean Grange, Ovingdean New Barn, and Pickershill Farms. (Upper Paythorne is itself 100% pasture but is part of a much larger holding with a very large arable component. Stanmer Home Farm is now split between two neighbour farms which respectively manage their portions as grazing or arable).
Only three of our major farms are based mostly upon grazing nowadays. New Barn Portslade runs sheep and cattle with horse grazing. Waterhall Farm has both sheep and cattle enterprises, alongside large-scale game bird shooting. Additionally, Patcham Court is now largely cattle and sheep grazed, with a small arable component. The farm is now spilt between three neighbour farms.
Northease Farm's organic level Brighton Downland Estate holdings are all grazing pasture.
Mainstream arable farming
There are three main models for UK cereal production - ONE: that of high input - high output conventional arable cropping, with its fertiliser and pesticide dependent usage of modern high yielding hybrids, with repeated diesel-fuelled applications; TWO: that of its less wasteful 'regenerative farming' alternative; and THREE: that of the main organic model which largely shares the other models' dependence on modern high yielding hybrid cereals, and also requires extensive areas of temporary grass leys and manuring.
Arable production on the Brighton Downs and Brighton Downland Estate is based upon a very limited range of crops - wheat, barley and rape, mostly. The wheat is for both human and animal foods, barley is for beer and animal feed, rape is for paints and other industrial products. In addition, some beans are grown, together with some other forage crops, and sometimes maize is grown for animal feed and for game bird shooting cover.
The major human food crop grown is wheat. It is grown using high yielding modern dwarf hybrids dependent upon artificial fertilisers and pesticides. (They are dwarfed to prevent lodging - falling over before harvest).
Cereal yields now have increased hugely on the Downs, and can achieve up to 10 tonnes per hectare of high quality wheat, against a national average of about 7.8 tonnes per hectare. These require the use of fungicides and pesticides and large nitrogen fertiliser applications. On the Paythorne Estate the traditional nitrogen application rate was 202 kg/ha. Even with new fine tuning[i] involving the planting of cover crops post-harvest, direct drilling, and replacement of granular with foliar applications to drive down nitrogen application rates, the total is still 169 kg/ha.
By contrast, most UK organic cereal agriculture is based on farm economies with a significant livestock component. The majority of organic holdings growing cereals feed the majority of their crops to animals. Some do not produce any grain at all for human consumption. Most organic wheat growing farms follow a long rotation of perhaps five years. Three years of that would be down to clover-grass leys, one to cereal or roots for animal feed, with one year of high quality wheat cropping.
Most organic mixed farming is heavily dependent upon grass leys, which are used for animal grazing and ultimately ploughed in to increase fertility. John Letts calculates that even if the UK was to stop feeding wheat to animals and halved the use of other cereals for animal feeds it would still need some eight million hectares of temporary clover-grass leys - a third of the entire country - to fertilise the land needed to grow enough food for everyone organically.
Continuous grain cropping
There is, however, another model for sustainability. This model is of continuous grain cropping, as developed by John Letts. It achieves continuous yields of three times that achieved by a rotational organic system without incurring any problems with disease, whilst building organic matter within the soil, and biodiversity above and below ground. Wheat yields of three tonnes per hectare are achieved on an on-going basis. These are much more than twice the yields of medieval cultivation using similar communities of co-evolved local wheat varieties, if medieval rotations are taken into account. They are three times the one tonne per hectare yields for rotational organic production, averaged over its cycle.
Continuous grain cropping relies on the use of genetically diverse and constantly evolving populations of traditional varieties of wheat, which Letts calls 'heritage populations'. Many of these varieties are long stemmed and deep rooted, as pre-modern wheats were, and thus produce extra residues at harvest. This high-carbon straw is left on the soil and ultimately - with the large root systems - ends up incorporated in the soil. (Take a look at Bruegel the Elder's famous 1565 painting 'The Harvesters' and you will see that the height of the wheat came right up to the shoulders of the reapers!!)
These co-evolved populations of seed wheat improve and change over time in different ways according to the host soils and local growing conditions. They obviate farmer's dependence on major seed suppliers. All crop residues are left on the soil surface after harvest to improve soil quality, no ploughing or inter-row tillage is required, and each new crop is planted in early autumn and under-sown with short white clover.
This regime leaves the ground with nitrogen levels in surplus (helped by natural deposition from the atmosphere) without any need for the use of artificial fertilisers or agri-chemicals.
This system obviates the need for set-aside beetle banks and flower margins to off-set intensive cereal production's 'green deserts'. The surface mulch of crop residues prevents fungal spores from splashing onto the crop from the soil surface, and an active community of micro-organisms digests the inescapable rain of spores that falls onto every field. Disease carrying pests are rapidly matched by an increase in predators. The genetically diverse crop can offer a community-level resistance to an attack, whereas a modern wheat variety relies only on genetic resistance bred into the crop - and agri-chemicals.
Avoiding the point...
The original objectives of agri-environmental support on our Downs (via the old ESA scheme - 'Environmentally Sensitive Areas') have been dodged by commercial farmers, who succeeded in getting the criteria for support modified to allow reversion to non-diverse - more commercial - grassland pastures on the Downs. These farmers had used modern commercial livestock breeds to graze the original botanically diverse reversion ESA pastures, and then complained when the livestock did not thrive there. Their priority was not consistent with the priority of the ESA scheme[ii], which was to conserve the high-nature-value chalk grassland resource.
Furthermore, the early ESA scheme was the pioneer, the first tentative step towards reversing post-war and EU CAP agricultural policy, so was never resourced and targeted, as it should have been, for the intensive and detailed work of ecosystem restoration that is needed today - scarification, seed strewing, plug and turf transfer and planting, exclusions and inclusions of stock, topical scrub replanting and major scrub removal, et al.
Commercial farmers, too, utilised their own versions of the ESA prescriptions, which minimised the contribution these new reversion grasslands could make to species-rich chalk grassland restoration, but maximised their commercial value.
The Paythorne Estate, with the support of the RSPB, took a different route. It negotiated a different farm plan on its high ESA Downland, with a mix of arable and pasture. They described their original ESA scheme reversion pastures as 'green concrete'[iv]. Thus, the potential for restoration of the unitary Down pasture mantle was destroyed and replaced with a mosaic of arable and pasture, with 'islanded' relict archaic chalk grassland[v].
By dropping the cultivation of beer barley and industrial rape[vi], and such wastage as game cover crops, the acreage of sustainable milling wheat could be ratcheted up much further. In a world economy moving towards food shortage and climate change the dedication of land to essential, locally retailed food crops and essential nature conservation rises higher as an imperative than that of recreational foods and drinks and non-essential industrial products.
By side-stepping the need for conventional organic cereal farming's extensive temporary grass leys continuous grain cropping maximises the leeway - the 'elbow room' - for landscape-scale restoration of species-rich chalk grassland. The chalk grassland ecosystem is the backbone high nature value ecosystem on our Downs.
Interest has been shown recently in the model of regenerative agriculture provided by the Kingsclere Estate in Hampshire[vii] where half of that large holding is dedicated to temporary multi-species herbal leys. Yet, to my knowledge, that estate has no archaic chalk grassland or similar long-standing semi-natural pastoral ecosystem, and thus has the 'slack' to dedicate large areas to rotational temporary grazing. It is not a model that we can use directly on the Brighton Downs Estate in that respect, where the key conservation responsibility of the City is to conserve and enhance the severely damaged and fragmented chalk grassland resource at a landscape scale.
That system offers ongoing threat to the purity of the chalk aquifer, continued declines - to extinction - of high value local species, ecosystems, and sites, and continued drift towards climate change - with diffuse pollutions, run-off, soil erosion, et al.
Instead we need a low input - low output model which marries the imperatives of local food production with those of ecosystem and landscape restoration.
We must use our Downs for food production, but we must use them too to conserve their internationally important pastoral ecosystem, and make that a truly public resource that all can wander and use as free people.
[ii] The South Downs ESA scheme aims came under three-fold headings: landscape, archaeology and wildlife. They supported the classic Downland landscape of the open sheep walks, with their scented, springy turf, upon which you could walk forever. They sought to protect the lumps and bumps, the ribs and knuckles, and the near-surface artefacts of the remaining archaeological/cultural heritage, and they sought to conserve and restore the extremely biodiverse wildlife of the chalk grassland ecosystem. The scheme had two tiers: ONE, nurturing the surviving assemblage of chalk grassland sites, and TWO, reverting arable ground to viable grazing pastures to stitch back together the fragments of neglected chalk grassland into a landscape-scale mantle. No consideration was given in the ESA scheme's early days to any specifically arable tiers.
[iii] At New Erringham Farm, for example, massive soil erosion problems (which would have caused major urban flooding if it had not been for the 'dam' created by the A27 bypass) had been addressed by reverting the farm's arable to ESA pasture. However, the five year break clause in the ESA agreement was triggered and the £125,000 ESA public conservation investment was ploughed up! For once this disgrace made national news, with Phil Belden on BBC R4 'Today' programme, and a major piece in the Times. As a result, the ESA scheme was improved at its five year reviews.
[v] The RSPB stance was that the ESA scheme just replaced one monoculture (arable) with another (grass and clover). They side-lined the ESA's gains for landscape and archaeology, but - more importantly - they ignored the potentials for wildlife with more intensive chalk grassland restoration in an improved South Downs ESA scheme. The narrow focus of sectoral wildlife organisations, like the RSPB and the Woodland Trust, offers recurring problems such as this.
[vii] See, for instance: "At Kingsclere, half our farm is planted with multispecies herbal leys: a diverse seed mixture of legumes, grasses and herbs. By rotating our leys with our crops and our livestock, and timing the rotations to let the plants grow, flower and put down roots, we keep our soil varied and nutrient-dense".