Agroforestry is a farming system that integrates crops and/or livestock with trees and shrubs. The beneficial results of such integration include such things as improved habitat for both humans and wildlife, improved water quality, and increased crop production. Just as importantly, the practice of agroforestry can provide farmers with diversified and more stable income sources.
Key Practices of Agroforestry
Alleycropping is when farm crops such as grains and vegetables are planted in the spaces, or "alleys", between rows of trees. Farmers determine the space between the rows based on the mature size of the trees.
Also referred to as 'shade systems', forest farming is the sustainable, integrated cultivation of both timber and non-timber forest products in a forest setting. Some examples of non-forest crops that can be grown in a forest environment include certain wild berries and fruits, maple syrup, mushrooms, and various plants used for landscaping, floral greenery and pharmaceuticals.
Riparian Forest Buffers
Riparian zones are important environmental habitats as they protect aquatic environments like streams and rivers from excessive sedimentation, polluted surface runoff and erosion. They supply shelter and food for many aquatic animals as well as shade that is an important part of stream temperature regulation.
Riparian forest buffers, sometimes called filterstrips, are created when trees, grasses, and/or shrubs are planted in the areas along streams and rivers. These plantings catch soil, excess nutrients, and chemical pesticides before they enter waterways. Such plantings also physically stabilize streambanks, thereby preventing or reducing erosion and flooding. These areas can also often generate income from both timber and non-timber forest products.
Silvopastoral agroforestry is a system that combines the grazing of livestock on forage crops or pastures within a larger system of trees or shrubs. The most common livestock utilized in the creation of a silvopasture are cattle, goats and sheep.
Sometimes called shelterbelts, windbreaks are rows of trees planted along the edge of a field. The trees help reduce the effects of wind on crops and/or livestock. These effects include soil erosion, water evaporation, and snow and freezing winds. Additionally, insects that protect and pollinate crops can find permanent homes in the windbreaks.
Benefits of Agroforestry
The benefits of agroforestry are supported by studies in many disciplines, such as forestry, fisheries and wildlife, entomology, plant pathology, agronomy, animal science, horticulture, soils, atmospheric science and agricultural economics.
The integration of trees and shrubs with other plants and/or livestock can:
- create additional sources of income for farmers
- increase farm job stability by spreading farm labor throughout the year
- increase productivity on farmlands
- increase biodiversity
- increase advances in medicine by increasing access to pharmacological trees and shrubs
- reduce hunger and poverty by increasing production of products for both consumption and sale
- improve farm soil fertility
- increase protection of soil, water and wildlife
- reduce the speed of climate change, since trees take up and store carbon at a faster rate than crops.
Although its many benefits are clear, the science and management of agroforestry systems is just now beginning to gain real notice from the agricultural and forestry communities. It is clear that this is a field of biology that should be the focus of much greater attention from the scientific and environmental communities.