Tree hay – the answer to agriculture’s prayers?
Friday 17 February 2012
Conventional farming around the world is facing a crisis. The consolidation of power in the hands of a few transnational companies, reliance on finite chemical inputs and fragility in the face of climate change have led to calls for an end to “business as usual” and an increase in innovative environmental practices.
One exciting project in West Sussex, led by an eminent tree expert, may hold some of the answers for creating more resilient, low impact systems by looking backwards and applying scientific knowledge to ancient farming techniques.
Charlie Burrell, of Knepp Castle estate in West Sussex, has begun a rewilding project on the estate he manages “Where natural processes predominate and long term financial stability is achieved outside of a conventional agricultural framework” which he claims is replicable throughout the English lowlands. Part of this project is reviving the use of trees for fodder or ‘tree hay’, which has benefits for animals, the environment and can even prevent flooding.
Tree hay stored and fed to animals is thought to have been one of the earliest practices in livestock farming. It is thought that early farmers, who would have seen animals browsing on trees and bushes, were able to use stone tools to hack off and preserve branches, complete with leaves, long before the development of tools sophisticated enough for harvesting grasses.
Ted Green MBE, founding member of the Ancient Tree Forum, who is involved with the Knepp project, spoke to Farming Online about the benefits, history and possible future of tree hay. He explained that a 3,400 year old pollarded oak has recently been found in the river Trent.
Mr Green said the use of tree hay is perhaps as old as the original subsistence farming, that the practice has probably existed ever since animals were domesticated. He said, “Tree fodder presumably predates grass hay by millennia.”
Mr Green continued, “We didn’t decide livestock should only eat grass until the war; until then they lived on herb and flower rich pastures which contained up to 70 per cent woody tissues.” The preferred trees used for fodder were ash, elm and holly (mainly for winter); these were pollarded (cut 2m above ground on a 2 to 3 year rotation dependant on growth) or managed as shreds (taller trees, climbed annually and cut at the top, or shroud, for tree hay). The process is thought to have died out as turnips gained in popularity as winter fodder.
The material was used to feed horses, cows, deer and sheep, but is suitable for all grazing and browsing animals. The Knepp project is using tree hay as winter feed for Exmoor ponies and English longhorn cattle. The trees are cut in the last week of June or July, dried like grass hay and stored for winter feed. Mr Green said, “If you cut a branch in summer, and the leaves stay on the branch, it preserves the minerals and nutrients, the same as with grass hay.”
Benefits of tree hay
He said that feeding animals tree hay had yielded excellent results, as the material provides a range of nutrients which the animals cannot get from limited grassland produce without the need for added suplements. Mr Green commented, “Tree fodder will always give animals minerals, nutrients and roughage, which they can no longer get from feed from man-made, destroyed pastures, called ‘improved’ grassland, which need to be supplemented with other feeds.”
The material provides a good supply of protein for animals; the practice is still used in arid regions around the world, where trees provide an excellent source of moisture. In arid countries, during the summer, and at high altitudes in remote parts of Europe and elsewhere, tree foliage may provide over 50 per cent of feed for ruminants. The fact that trees provide much needed moisture in areas where it is scarce could be of benefit given that the trend of drier summers in Europe may affect grass yields.
In France, during the last serious drought year of 1976 when there was very little other green matter available, farmers in Brittany took to feeding their stock leaves and branches, returning to the traditional practice of pollarding for fodder.
Tree hay also has implications for disease control. There have been reports of liver fluke increasing in areas of Wales and related parasites are proving more difficult to kill on conventional farms due to growing antibiotic resistance in a number of species. However, certain species of tree have been fed to lambs to rid them of gastrointestinal parasites such as worms and liver fluke. Tannins in tree hay have been shown to be excellent wormers; young oak which is still fresh, is particularly useful for this.
As well as providing sources of nutritious fodder during the winter, reintroducing working trees into the landscape has wider environmental benefits. The trees fix nitrogen to promote growth of crops underneath them and reduce soil erosion. The trees’ nitrogen fixing can aid the growth of leguminous plants which are also good sources of protein for livestock. The European Parliament recently passed approval of a report by Green MEP, farmer and rapporteur José Bové which called for further research into increasing legume cultivation to provide home-grown sources of nutritious feed.
Feeding the right type of animal on trees has been shown to provide further beneficial effects, including reducing the likelihood of flooding. In North Yorkshire, it is thought that flooding can be exacerbated by the activity of sheep, which graze the moorland compact the soil, reducing its ability to retain moisture.
The process also provides benefits for climate change, as trees are an excellent form of carbon sequestration. The circular process of feeding stock from trees and using their nutrient-rich manure as fertiliser has implications for low-impact farming; an example of the sort of practice which will be needed to achieve sustainability goals.
Extolling the nutritional benefits of the practice, Mr Green said, “It provides an organic food source, with good nutrients and minerals which they couldn’t otherwise get, unless from an ancient herb rich meadow or pasture. Even so, trees’ roots go deeper and get nutrients which aren’t available to meadow species.”
A possible future management system?
There have been widespread calls to look into revolutionary new food production practices, with the global population expected to rise by a further two billion by 2050, and in the face of widespread environmental degradation. Projects such as this could help agriculture shift towards a more equitable and resilient model, which considers environment and social justice as well as financial profit.
In 2008, Miguel d'Escoto Brockmann, then President of the General Assembly of the United Nations, lamented the naked profiteering which has led to stagnation in agriculture, "The essential purpose of food, which is to nourish people, has been subordinated to the economic aims of a handful of multinational corporations that monopolize all aspects of food production, from seeds to major distribution chains, and they have been the prime beneficiaries of the world crisis."
Last year’s National Ecosystem Assessment recommended that farmers in high input, low profit systems including sheep farming in the hills of North Wales reforested some of their land to provide carbon storage, wildlife habitats and recreation areas for nearby cities. It may be that agroforestry systems such as this provide a viable alternative.