When we think of Scotland, images of sheep in fields are likely to come to mind. That is because land for keeping sheep occupies a high portion of the nation’s area.
Using that land to combine trees and agriculture, known as agroforestry, could be an opportunity to reduce greenhouse gases levels while benefitting farmers, their animals and agriculture resilience.
Agroforestry can be done either by adding shrubs or trees to land used to grow vegetables or animals, or by moving livestock to woods. Trees can be widely spaced or in groups and hedgerows or windbreaks can also be used.
Products resulting from agroforestry are already successfully sold in UK supermarkets. For example, Woodland Eggs come from chickens that have access to woodland, as part of a partnership between a supermarket chain and the Woodland Trust.
There is growing interest in making farming more sustainable and contribute to Scotland’s ambitious goals of reaching carbon neutrality by 2045. In this blog post we give an overview of findings from research on the topic that has been commissioned by ClimateXChange.
Agroforestry systems for Scotland
Carbon benefits can be achieved fastest in highly productive lowland areas. Adding plants that serve as windbreaks and buffer strips is likely to further increase the amount of greenhouse gases captured. Hedgerows also have strong emissions mitigation benefits, but their financial viability is unknown.
This approach can bring financial benefits for farmers who can have an additional source of income from fuel, timber and fruit production.
Combining sheep and trees on the same land is economically viable for farmers while also helping Scotland reduce its greenhouse gas emissions.
Other approaches work as well. Studies reviewed for ClimateXChange have looked into different types of agroforestry system in the Scottish uplands and lowlands, and for a range of tree species. They found that all systems bring economic benefits for farmers, with only a few specific exceptions for land with vegetable crops. Furthermore these benefits are better than those from conventional agriculture and forestry.
Resilient farms and soils
Livestock productivity does not seem to be affected by introducing trees in farms, while there is an extra benefit of trees growing better when livestock is present. Trees also provide shelter and shade for livestock, and can reduce ammonia emissions, which harm people’s health as well as sensitive habitats.
Agroforestry can also make farms more resilient to climate change given that trees help prevent floods, increase biodiversity and make soils more stable and fertile.
These benefits translate into savings. For instance, soil erosion in Scotland costs up to £50 million each year, so prevention has clear economic benefits.
However, before planting trees there are some things to consider to maximise environmental benefits. Disturbing soil to plant trees can release carbon dioxide back into the atmosphere and it may take several years to sequester it back into the soil, depending on how many trees can be planted. So, it is important to consider original land use, soil type, planting method and type of agroforestry, as these may influence how much carbon is released.
Barriers for adoption
Whether farmers are willing to adopt agroforestry depends on the farming system they use, where they are, resources available to them, constraints and their mindset and priorities.
Introducing trees on a farm brings additional costs in the initial years owing to tree planting and establishment costs, while it can take years to generate income from selling tree-related products. However, in the long run agroforestry has higher economic benefits than conventional agriculture.
Financial support for land managers includes schemes that are directly targeted at agroforestry, for example the Forestry Grant Scheme support for agroforestry to help create small-scale woodlands within sheep grazing pastures, with others being more directed at hedge or woodland expansion. Researchers suggest that Payments for Ecosystem Services (PES) schemes, including the Woodland Carbon Code, could help make agroforestry more attractive for farmers.
Looking to the future, the potential for agroforestry will be influenced by a range of factors including changes in the price of timber, farm subsidies and carbon markets.
Featured research
Understanding carbon sequestration from nature-based solutions
The potential for an agroecological approach in Scotland: policy brief
Agroforestry in Scotland – potential benefits in a changing climate