A Harvest for Future Generations - #AgroforestryWales
Read our campaign blog here: https://www.woodlandtrust.org.uk/get-involved/campaign-with-us/our-campaigns/agroforestry-in-wales/
What is Agroforestry?
Simply put, agroforestry means combining agriculture and trees; farming systems that combine trees or shrubs with agricultural crops or livestock.
What are the main different sorts of agroforestry that are most applicable in Wales?
Agroforestry includes traditional practices that are easily recognised in the Welsh landscape, such as farm hedgerows, as well as newer innovative systems such as silvoarable cropping, a method of growing alleys of productive trees through arable land. In other countries, including France and Spain, integrating trees and agriculture through agroforestry is a normal practice, yet in Wales this is not the case. There are five distinct types of agroforestry commonly recognised:
- Silvopastoral: trees and livestock. This is commonly seen in Wales in wood pasture and parkland landscapes where controlled grazing takes place under a discontinuous tree cover. Over centuries this has created the historic and distinctive landscape of the ffridd or coedcae, the terms for the partly wooded zone between enclosed lowland fields and the unenclosed and largely tree-less upland. Tree cover in these landscapes has traditionally waxed and waned according to grazing pressure. Where it has been relatively high only thorn trees may survive and such thorn covered hillsides are sometimes called the Welsh savannah.
- Hedgerows, shelterbelts and woodland buffer strips. This is an established approach to livestock farming that is a form of agroforestry that makes use of linear woodland to support the farming system through providing shelter, shade; managing water, sediment and nutrient flows, and providing resources such as firewood and wood chip. In this system the wooded areas are actively managed but not usually grazed.
- Silvoarable: the combination of trees and crops. In Silvoarable systems agricultural or horticultural crops are grown simultaneously with a long-term tree crop to provide annual income while the tree crop matures. Trees are grown in rows with wide alleys in-between for cultivating crops. This is not commonly seen in the UK but some innovative farmers are exploring the benefits it offers in a changing climate for management of soil, water runoff and provision of shade.
- Forest farming: cultivation within a forest environment; Not commonly practiced but the Star Tree project has. Also this category can include orchards, which often used to be grazed and with newer examples laid out with rows of fruit and nut trees grazed underneath by sheep and sometimes cattle.
- Home gardens: small-scale production in mixed or urban settings. There is widespread and increasing interest in food production in urban settings and gardens, often mixing crops with a wide variety of trees.
Haven’t farmers been doing agroforestry for centuries?
Yes they have, as is shown by the wood pasture of the fridd or coedcae on the upland margins and in the form of trees and fragments of woodland surviving within fields or enclosed parkland, and in remnants of grazed orchards. This once mainstream approach has been discouraged by decades of policy which has pushed farmers towards specialisation and away from integrating their farm and woodland management.
Is a hedge agroforestry?
A single hedge isn’t, but where hedges are used systematically across the farm as part of farm management for example to provide, shelter, shade (“living barns”), habitat for wildlife, and pollinators, fruits and nuts or wood chip that can be described as an agroforestry system.
What are the benefits of agroforestry to the farm business?
- In Wales the benefits of agroforestry are recognised and promoted by the Farming Connect technical advisory service. They note the benefits shade and shelter in reducing energy requirements and feed input costs, and increasing feed conversion rates and weight gain. Reducing the effects of wind chill (and thus hypothermia) can also increase lamb survival rates, particularly in the early stages after birth. The presence of trees also increases the rate of water infiltration to soil, which can reduce standing water and consequently incidence of lameness and liver fluke in livestock
- Farming Connect also note that certain tree species may also be helpful in terms of ‘self-medication’, where animals can forage on material with beneficial properties. One example of this is willow, which has anti-helminthic properties. The degree of benefit that this may offer however requires further research to ascertain.
- Browse from trees and shrubs can play an important role in feeding ruminants and is explored further in this technical note on agroforestry for livestock systems.
- The benefits of planting additional hedges and shelterbelts have been fully explored by the Pontbren Farmers project in Montgomeryshire. They found that the approach enabled them to explore ways to reduce costs and add value and benefits included helping a move to hardier local breeds, reduction of flash flooding and development of a wood chip bedding system.
- Research at Pontbren showed that tree planting resulted in significant flood attenuation at the small scale and that that tree and hedgerow planting to reduce run-off can also help to mitigate diffuse pollutants such as sediment, phosphorus and pesticides, and can help to change sediment yields. Riparian planting was also shown to stabilise riverbanks and to offer refuge for wildlife.
- A comprehensive and fully referenced review of the benefits of agroforestry is available in a recent policy briefing by the Soil Association and the Woodland Trust. Benefits highlighted include:
- Growing two crops from the same land such as rows of fruit trees through arable crops, or combining livestock and timber trees can increase total yield and on-farm productivity.
- Productivity increases under agroforestry can be significant, in some cases up to 40%.
- Hens ranging on land with 20% tree cover have been found to have increased laying rates and higher shell density meaning higher output, fewer second eggs, and reduced losses.
- The careful siting of trees on farmland can improve soil infiltration and water retention, reducing the impact of flooding by increasing the capacity of the land to retain water.
- Trees integrated into arable settings have been proven to reduce soil erosion by up to 65%.
- In a recent review of silvoarable systems in temperate climates it was found that nitrate leaching was reduced by 46% in Canada and 30% in France.
- The leaves and bark of trees can provide increased nutritional diversity, improving animal health and they offer the potential to alleviate the use of antibiotics in animal agriculture.
- Creating tree belts and thick hedges can provide a suitable bio secure boundary around a farm. There is also evidence that trees in general can act as a buffer to the movement of harmful bacteria, such as E. coli through ground water
- Well designed and maintained green “tree infrastructure” may make your farm more attractive for a bed and breakfast business and make it more attractive to property buyers. Guidance on valuing the amenity asset value of trees is available from RICS.
How else can agroforestry help increase climate resilience?
Our policy briefing referred to above notes that:
- Integrating trees into farms at a significant scale could dramatically increase the amount of carbon sequestered on farms compared to monocultures of crops or pasture. The Committee on Climate Change highlight that conversion of 0.6% of agricultural land area to agroforestry would contribute significantly to meeting the fifth carbon budget target by 2030.
- Agroforestry systems protect soils from erosion by wind and water, as trees with long roots hold soils firm while increasing soil organic matter by adding decomposing leaf litter.
- Trees integrated into arable settings have been proven to reduce soil erosion by up to 65%. The UK government has committed to the ‘4 per 1000 initiative’ which aims to increase soil carbon stocks by 0.4% year-on-year. Agroforestry can make an important contribution to this goal and is a key way in which farming can mitigate climate change and become more resilient to extreme weather.
What are the conservation benefits of agroforestry?
- Agroforestry has been demonstrated to benefit farmland wildlife, with the potential to increase average biodiversity more than two-fold. It can provide the connectivity and food sources for wildlife in farmed environments that are crucial to achieving targets under the UK’s commitment to Biodiversity 2020, and to delivering the Welsh Government’s Action Plan for Pollinators.
- 130 priority Biodiversity Action Plan species, of which 104 occur in Wales, are known to be significantly associated with hedgerows. Hedgerows are of particular importance to the conservation of threatened lichens (10 species), invertebrates (72), reptiles and amphibians (5), birds (20) and mammals (11).
- Wood pasture is of huge biodiversity value in its own right and many of Wales’ internationally important heritage of ancient trees is associated with wood pasture.
- Integrated approaches to land management are popular with the public, agroforestry can harness public appeal towards ‘managed rural landscapes’ and offer an ‘integrative strategy for landscape protection and management’.
- In conclusion, more trees and hedges (at least 3 metres wide and tall, including mature trees within them), tree belts, streams, planting along water ways and along roads and tracks all create homes for wildlife and very important wildlife corridors. These all assist with its movement from place to place, providing better protection from natural predators.
What about wildlife that causes damage?
Benefiting wildlife also means more habitat for rabbits, grey squirrels, deer and other species that may do damage. In a landscape that contains more connected and complex patterns of habitats these species may have more options and damage may be less prevalent and predators such as pine martins will do better. However some species will continue to need control and these needs to be part of managing the land. We describe our approach in our position papers on deer and grey squirrels.
Why aren’t agroforestry more widely practiced?
- Farms have specialised, moving away from mixed farming systems which better match agroforestry. The intensification of farming and the Common Agricultural Policy have encouraged this and favoured a separation of farming from tree management.
- The current farm subsidy system actively incentivises the removal of trees from farms because any land under a tree canopy has to be removed from the area on which subsidy is paid.
What about towns and cities?
The combination of trees with other crops can be an efficient and attractive way to make the most of limited space for food production within towns and cities e.g. hedges around allotments can provide shelter, a source of pea-sticks and nectar to encourage pollinators.
What is harvested?
The tree component of agroforestry can provide various products, including timber for product (crafts and construction), firewood and wood chip, forage, fruit, or their use may simply enhance the harvest of the mainstream farm product.
Why is this important for future generations?
- We are seeing a wholesale decline in wildlife across the country. Most of this decline has happened on agricultural land, if only because 80% of Wales is managed for food production.
- We are also seeing a substantial loss of trees and hedges from the countryside and there is a need to act to replace millions of trees. Recently this has been exacerbated by the accelerating spread of tree diseases from other parts of the world, such as ash dieback.
- A marked increase of agroforestry systems applied to agricultural land management can, as Farming Connect note, “…. may offer an alternative management system, which meets the requirements for reduced environmental impact, whilst improving the potential for farm business productivity”
- More trees on agricultural land will improve how our landscape looks. This will increase the desirability to create greater public and community access to it. Again it is proven that access to quality green infrastructure has huge benefits to our well-being.
How can I help?
- Write to your AM and MP asking them to help ensure that a new land use policy encourages more trees on farms
- Spread the word on all social media channels. The Twitter hashtag is #AgroforestryWales
- If you manage land and use or are interested in adopting an agroforestry system please contact us: firstname.lastname@example.org
- Read more about the Trust's views on agroforestry: http://www.woodlandtrust.org.uk/blog/2018/03/agroforestry/