Biodiversity and Agroforestry
Forest gardens – an environmentally friendly way forward for all landowners
There is a simple way to save money, save energy, store carbon, provide local fresh produce and enhance biodiversity all at the same time – it is known as agroforestry. This is an internationally accepted term referring to the combination of agriculture and trees. Not the usual system of separate areas of land used for separate tree plantations, food crops and grazing areas – agroforestry combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy and sustainable land-use systems. It derives from the ancient system of forest gardens whereby the trees provide shelter, shade, ‘sun-traps’ and nutrients (drawn up through their roots from the sub-soil). Meanwhile, the vegetables and herbs and / or animals using spaces between and amongst the trees thrive and produce their own nutrients derived from the top-soil. Thus the need for fertilisers is reduced, if not eliminated. The increased biodiversity of the combination means more natural predatory insects and birds to eat the pests – thereby eliminating the need for chemical pesticides. The whole system can be any size from a small back garden to a vast estate.
Unfortunately current Irish Forestry Policy does not cater for agroforestry, although it is mentioned in Green Party forestry policy which is under review. It is also not catered for in the Rural Environment Protection Scheme, the Forestry Environment Protection Scheme or the Native Woodland Scheme. Irish Forestry Policy, the Forest Service and the timber industry do not even distinguish native trees, instead using the ambiguous terms ‘broadleaf’ or ‘deciduous’ which of course include monoculture plantations of non-native Sycamore, Beech, Maple, Sweet Chestnut, Walnut and Larch. Whilst these non-natives are undoubtedly useful for timber and could be incorporated into mixed agroforestry systems, they do little to benefit biodiversity because they have no history of association with our native insects, birds, plants or animals.
Agroforestry systems can be either ‘Silvopasture’ or ‘Silvoarable’. Silvopastures combine livestock grazing on forage crops or pastures within actively managed tree or shrub crops. Part of this management would involve regular rotation of fenced off grazing areas with protected trees. Silvoarable agroforestry comprises widely-spaced trees or groups of trees intercropped with arable crops. This builds on recent findings that indicate that modern silvoarable production systems are very efficient in terms of resource use, and could introduce an innovative agricultural production system that will be both environment-friendly and economically profitable. Growing high quality trees in association with arable crops may improve the sustainability of farming systems, diversify farmers incomes, provide new products to the wood industry, and create novel landscapes of high value.
Agroforestry systems increase species diversity within farming systems, providing for human needs while supporting wildlife, soil microorganisms, rural communities, farmers, economic interests, watersheds, clean air concerns, biodiversity, and more. Economic viability is an important aspect of the success of agroforestry projects. Knowledge, careful selection of species and good management of trees and crops are needed to optimize the production and positive effects within the system and to minimize negative competitive effects.
The objective is to provide a balanced environment, sustained yields, biologically mediated soil fertility and natural pest regulation through the design of diversified systems and the use of low-input technologies. Agroecologists are now recognizing that agroforestry mimics natural ecological processes, and that the sustainability of complex systems lies in the ecological models they follow. By designing farming systems that mimic nature, optimal use can be made of sunlight, soil nutrients and rainfall.
The International Panel on Climate Change (IPCC) asserts that , worldwide, agroforestry has the potential to remove 50 billion tons of carbon dioxide from the atmosphere, which is equivalent to replacing 1,400 large coal-fired power plants with gas-fired facilities. Meanwhile, the World Agroforestry Centre (ICRAF), based in Nairobi, Kenya, asserts that, if farmers were allowed to sell that carbon on global carbon markets, it could generate billions of dollars each year for poor people in rural areas. “Rewarding poor farmers for planting more trees would put money in their pockets while also helping to protect our environment and fight climate change,” said Prof. Wangari Maathai, the 2004 Nobel Peace Prize Laureate and founder of the Green Belt Movement International. “These long-term investments would truly benefit the entire global community.” The World Agroforestry Centre is the world’s leading research institution on the diverse role trees play in agricultural landscapes and rural livelihoods. As part of its work to bring tree-based solutions to bear on poverty and environmental problems, centre researchers – working in close collaboration with national partners – have developed new technologies, tools and policy recommendations for increased food security and ecosystem health. See
The Agroforestry Research Trust is a non-profit making charity, registered in England, which researches into temperate agroforestry and into all aspects of plant cropping and uses, with a focus on tree, shrub and perennial crops. See
In County Clare, the Centre for Environmental Living and Training (CELT) are working to encourage agroforestry as a way forward for all landowners. They especially encourage the combination of native trees and shrubs with organic vegetables and herbs. A native tree nursery has been established along with a small forest garden area producing fruit, nuts, vegetables and herbs. Also CELT have, in association with Just Forests, at Rhode, County Offaly, planted over 300 native trees and shrubs on half an acre as a wildlife area surrounding a vegetable garden. This will be carefully monitored as an example of what can be done on any small plot of land. There are now plans to develop larger areas of land that could also include coppice management of trees such as ash and hazel for a range of timber uses.
The above was put together from various sources by Bob Wilson (founder-member of CELT and a director of Clare Biodiversity Group)
Contact: Bob Wilson at