Search our website enhanced by Google.
- Home
- Knowledge library
- Greenhouse gas mitigation through agroforestry
Greenhouse gas mitigation through agroforestry
How combining trees and farming can capture carbon and add resilience to your land.
Environmental and farming benefits
Growing trees in tandem with the farmed environment is becoming more common in UK farming systems. It combines food production with the benefits trees offer for farmland resilience, carbon capture and other environmental goods.
Find out more about agroforestry
The benefits of agroforestry
Agroforestry can mitigate climate change by reducing atmospheric concentrations of carbon dioxide (CO2), by sequestering carbon in woody plant tissue via photosynthesis, and in surrounding soils.
How much more can be absorbed by including trees will depend on factors such as the initial levels of soil carbon and nutrient status, and how quickly the chosen species of trees grow. Though, soils that already have high carbon content may initially lose some until newly planted trees become established.
Agroforestry, whether that’s faster-growing broad-leaved species than already exist on a farm, or productive fruit and nut trees, is also seen as a valuable tool to making farmed landscapes more resilient to weather extremes by helping to manage water flow and improve soil health and nutrient cycling.
From lines of alley trees and wood pasture to shelter belts and hedges, agroforestry is an important tool for helping farms become resilient to changing weather patterns.
Trees mitigate against soil erosion as their deep-reaching roots bind soil together, helping water infiltration rates and to slow sediment flow, reducing soil and water movement and, consequently, run-off which can otherwise have a knock-on impact on water quality, while reducing nitrogen leaching.
Those deep roots also draw up nutrients from further down in the soil, bringing them closer to the soil surface where arable crops and grass plants can access them.
Strategically planting trees in strips as a shelter belt will provide protection for livestock and arable crops from extremes of rain, heat and wind.
That protection from the weather might take the form of a natural windbreak to reduce lodging risk and subsequent yield losses in crops, and providing shade and shelter for animals to mitigate the risk of heat stress or hypothermia.
Trees and other woody vegetation also play an important role in supporting biodiversity and providing habitats for a host of beneficial insects.
By increasing habitats for predators to act as pest controls, they may also protect crops from damage.
As well as recognising how trees can mitigate the effects of climate change on their businesses, environmental payments have helped to encourage farmers to adopt agroforestry principles.
In fact, payment schemes and structures are likely to influence how agroforestry develops in the UK, steering farmers on how and where to incorporate trees into the farm landscape.
Beyond payment schemes, trees can bring in additional income if they grow sellable crops such as fruit.
Types of agroforestry
The two main types of agroforestry in the UK are silvopasture and silvoarable:
- Silvoarable is where trees and crops are grown on the same land. Trees are often planted in rows so farm machinery can move easily between them
- Silvopasture is where trees are combined with livestock grazing
Other forms include:
- Hedgerows and buffer strips – commonly used on tracts of unproductive land, field margins and along watercourses
- Forest farming – cultivation within a forest environment
There is no official definition of the minimum tree cover required for agroforestry. Therefore, any farming landscape that aims to incorporate trees or woody vegetation could fall under this heading.
The benefits of integrating livestock and trees (Sustainable Food Trust)
Planning and designing agroforestry systems
- Define your objectives – Agroforestry projects should be guided by the intended purpose of integrating trees because the type of trees and where they are introduced will very depend on whether they are needed for shelter, increasing carbon sequestration, to provide new revenue steams such as from the sale of nuts and fruit, or a combination of these outcomes and more.
- Consider timeframes and support – Considering the timeframe for achieving the result is also important at that stage as is researching possible sources of advice and any financial support that may be available.
- Design considerations – If the scheme progresses to the design stage, there is a lot of think about – for instance will the trees be planted in rows, as clusters, or on their own, and the density of the planting.
- Field integration – As the aim is to integrate trees into land that is actively farmed, allowing sufficient space for field operations without the necessity to incur the cost of specialist machinery is sensible. Make sure the layout fits the existing field system.
- Layout and orientation – Aspect and orientation are important considerations too, for example rows of trees are best situated to be parallel with the longest axis of the field while a north–south orientation suits apple trees
- Climate and sunlight factors – Local climate and the movement of the sun throughout the year needs to be thought about to ensure crops get enough sunlight at the right times of year. Prevailing winds or air currents may be important also.
- Species selection – Select species and varieties that suit the chosen operation - species choice, specifically how trees will interact with crops, livestock and environment, needs careful consideration as does demand for any end product produced by those trees.
- Site conditions – Factor in soil type and the altitude of the chosen site. Investigating how different species perform locally and selecting fast-growing, disease-resistant varieties that suit land will give an agroforestry scheme the best opportunity of succeeding. Site factors such as soil type, elevation and current land use will influence the species chosen. Take advice on varieties from a reputable supplier, what are the best matches for the farm.
Due diligence at establishment is essential – trees need to be protected from livestock and/or weed growth at this critical phase, therefore a management plan is essential.
See our getting started in agroforestry guide
Find out more on reducing emissions on farm
Further information
The Agroforestry Handbook (Soil Association)
The Agroforestry Handbook (Agricology)
