Guide to Agroforestry
Kiss the Ground’s Guide to Agroforestry examines the core systems and practices of agroforestry and how they are applied in a regenerative context to build soil health, increase on-farm resiliency, and mitigate the effects of climate change.
What is Agroforestry?
Agroforestry, in its simplest terms, can be defined as “agriculture with trees.” Its practices range from using trees as windbreaks to modeling entire production systems after the natural forest ecosystem. Indigenous cultures and smallholder farmers have been interacting with nature in a restorative, reciprocal manner for thousands of years, from Europe to the Amazon, in both temperate and tropical climates. We have the opportunity to blend indigenous wisdom with science and technology to rapidly transform the way we practice agriculture around the globe, creating an abundant future instead of one of scarcity.
As populations continue to rise, we must greatly increase food production over the next two decades to achieve food security globally. This will require an agriculture system that can “multi-functionally” increase food production, while at the same time enhance social and environmental outcomes. Trees simultaneously protect against soil erosion, filter the air, feed above- and below-ground organisms, provide shade and building material, produce food and medicine, and provide a plethora of other environmental, economic and societal benefits.
In its highest form, agroforestry is the modeling of our agricultural production after the forest ecosystem.
Most people are unaware of the impact agriculture has on our planet. The way we currently grow the majority of our food, fiber, and fuel is damaging our planet’s ecosystems at an alarming rate through loss of topsoil, loss of biodiversity, desertification, habitat destruction, and air and water pollution. This is not a new phenomena, but has been going on for thousands of years due to a poor understanding of how soil and ecosystems function. Our current large-scale “conventional” agriculture systems are arguably one of the most destructive human activities on the planet. But part of what makes agriculture so impactful is its sheer scope and scale. Done right, agriculture could be a force for restoration on a massive scale.
In terms of climate impact, trees are the most underrated solution to reducing carbon in our atmosphere. One tree is capable of absorbing approximately 50 pounds of CO2 per year. Imagine a farmer growing a crop without trees. The crop can only capture so much sunlight because of its height. But, if the farmer adds in rows of trees the system will capture more sunlight. Farmers, growers, and gardeners should consider themselves sun harvesters, and the way to harness the most solar light is via plants and trees. Through the process of photosynthesis, plants and trees pull carbon from the atmosphere and store it underground.
Trees are fundamental to any terrestrial ecosystem and necessary to improve soil health outcomes. Trees provide shade, windbreak, and habitat to other species, as well as sequester carbon from the atmosphere. Further, trees prevent erosion and water loss due to wind and keep the temperature cool. Well implemented agroforestry offers higher water infiltration rates and improved nutrient cycling. But there is no one-tree fits-all approach to diversified, integrated agroecological systems. Each farm is unique, and the combination of crops and trees that are best suited for that particular context cannot be universally applied to the ecology of another farm.
As we look to mimic the natural ecosystem of the forest, it is important to remember that a forest is more than just a collection of trees. Forests are often composed of multiple layers of vegetation, animals, fungus and other microbes converting leaf and woody material into soil. Most importantly, the interconnectedness of these elements in both form and function is what creates healthy forest ecosystems. As we design agroecosystems like agroforests, we must ask ourselves how we can put these elements together to foster these associations.
Watch: Life in Syntropy, by Agenda Gotsch
In the wild, forests are created by the natural succession of species, each occupying a niche in time and space. By employing nature’s model of succession in the establishment phase of the agroforestry design, it is not just the end result of an intact food forest that is regenerative, but also the pathway we take to get there.”
— John Parziale, Director of Agroforestry, Common Ground Kauai
Both developing and developed countries are increasingly looking to agroforestry as a land management system for climate change mitigation and adaptation. Agroforestry not only sequesters carbon and reduces CO2 emissions, but it also minimizes soil loss from erosion, improves nutrient cycling, enhances soil fertility and increases biodiversity by supporting pollinator and wildlife habitat. These benefits make farmers less susceptible to extreme weather events, like drought, fire and flooding, while improving yields, reducing chemical inputs, and strengthening food security.
Read: The Carbon Farming Solution by Eric Toensmeier
How it Helps with food security
In order to meet the demands of a rapidly growing population and increase food production over the next few decades, we must turn to multifunctional forms of agriculture that work to simultaneously increase crop yield and enhance ecosystem services like improved soil function, reduced soil erosion, and recharged groundwater supplies. Studies show that the adoption of agroforestry can increase yields by a factor of two, and that these yields are sustainable long term as agroforestry enhances soil fertility.
With climate change, whether it’s extremely dry or extremely wet, the forest is a very stable ecosystem. The food coming out of there is much less vulnerable than our cropping systems.”
— Steve Gabriel, Mushrooms and Agroforestry specialist at Cornell’s Small Farms Program
Design & Other Considerations
Before planting an agroforest, it is important to consider the spatial layout and orientation of the individual specimens and how they will interact with each other. This is especially important for long-term specimens that will grow to their climax stature. Short and medium term specimens can be placed to occupy a niche in time and space as dictated by their time to harvest.
Design resources, such as AgroforestryX, can assist with species selection, spacing, and long term planning. The Savanna Institute’s Planting Tree Crops guidebook for designing and installing a farm-scale edible agroforestry operation will walk you through site evaluation, provide species profiles, outline livestock opportunities, and journey deep into the opportunities of perennial agriculture. You may also want to explore other considerations such as food safety, long-term leases, and financing options.
Agroforests are an important solution to the multifaceted destruction that agriculture inflicts on the natural world. However, as much as ecological knowledge has progressed we still have an incomplete understanding of the inner workings of ecosystems and their complex interactions. Therefore, it is irresponsible to convert intact forest ecosystems, especially those with a high concentration of native or endemic species, into agricultural systems. A more appropriate context for an agroforest would be a restorative practice where agriculture has already displaced natural ecosystems or in the case of windbreaks, riparian areas or silvopasture, where the addition of trees will enhance the existing ecology (stabilizing soil, cycling nutrients, creating microclimates).
When looking at the scale of a farm or ranch, agroforestry incorporates five key components. Your management protocol may include all or some of these practices depending on your context. Not all of these principles must be used at the same time, although they tend to work more effectively in combination.
Alley Cropping is the cultivation of crops in the alleys between regularly spaced rows of trees or shrubs. Often these alleys are oriented on contour lines so that they intercept surface water run-off. The tree lines can also serve as wind protection and partial shade, which help to conserve water. If the trees and crops are not in defined rows and alleys, it would be more appropriately called intercropping.
Windbreaks are strips of trees and shrubs designed to enhance crop or livestock production while providing ecological benefits such as reducing water loss from soil and crops, preventing wind related soil erosion, building soil organic matter from fallen leaves, increasing biodiversity, enhancing pollinator habitat, and providing wind protection and shade for animals and plants. Trees and shrubs in a windbreak can also provide yield of their own such as timber, food, and medicine. Windbreaks are also referred to as shelterbelts, hedgerows, vegetative environmental buffers, or living snow fences.
Riparian buffers are strips of trees or other permanent vegetation, alongside a stream, lake or wetland. These buffers can help filter farm runoff while the roots stabilize the banks to prevent erosion and soil loss from flooding events. These plantings can yield harvestable crops and provide wildlife habitat.
This perennial system features multiple layers of vegetation, closely mimicking the structure and functions of a natural forest ecosystem. This layering of trees and crops can sequester carbon and produce high yields and diversity. Especially well suited to the tropics, this type of agroforestry restores land negatively impacted by overgrazing and monocrop agriculture. Successional and “Syntropic” systems are multi-story agroforestry concepts that emulate the way forests are created in nature through the process of ecological succession. This is the evolution of a community of plants, animals, and fungi toward a climax forest. This evolutionary process can be managed for yields at all stages of development.
Silvopasture is the practice of integrating livestock grazing and trees into the same agricultural operation. Livestock makes up a huge portion of agricultural land. About 77% of global arable land is used for grazing livestock or for animal feed production so it must be managed properly. Project Drawdown rates Silvopasture was as the top agricultural solution to mitigate the impacts of climate change because of its potential to sequester high amounts of carbon and increase meat and dairy yields.
Picture this: a tree crop, whether grown for timber, fruit, or nuts, integrated with livestock (perhaps sheep, chickens, ducks, turkeys, or pigs) roaming underneath the trees. Both the animals and the trees benefit from each other in a symbiotic relationship. The trees gain nutrients from the animal’s fertilizer, and the animals benefit from the tree’s shade, windbreak, and forage.
Within a regenerative grazing system, rather than releasing thousands of animals on a vast piece of land, a rancher will fence them into a smaller section, or paddock, to impact it heavily for a short duration of time. This rotational grazing practice mimics the ecological interaction between herds in the grassland ecosystem, where grazing animals, grasses and trees have co-evolved over eons.
The success of an operation will depend largely on your familiarity and experience with the dynamics of managed grazing, forage growth, and tree establishment. Timing is of the essence to manage appropriately and avoid damage to trees and other crops. It is difficult to maximize both livestock and tree production at the same time, so you will be faced with some tradeoffs. Lastly, it is important to consider the long term commitment and strategy required to implement this type of system – trees don’t grow overnight!
Pastures with trees sequester 5 to 10 times as much carbon as those of the same size that are treeless while maintaining or increasing productivity and providing a suite of additional benefits”
— Project Drawdown
How you can help
Feeling inspired and motivated to see the possibilities of regenerative agriculture come to fruition? You’ve already taken the time to understand agroforestry at an “overstory” level. Further educating and inspiring yourself is a great first step. Here are a few ways:
- Agenda Gotsch
- Agroforestry Partners (Financing)
- Agroforestry Resource Center (Cornell Cooperative Extension)
- Agroforestry Network
- The Center for International Forestry Research (CIFOR / World Agroforestry)
- The Center for Agroforestry (University of Missouri)
- Interlace Commons
- Jungle Project
- NCAT, ATTRA Sustainable Agriculture – Quick Tips for Agroforestry
- Propagate (Financing)
- Reforestation World
- Savanna Institute
- Trees for Grazers
- USDA Forest Service National Agroforestry Center
- VI Agroforestry
Director of Agroecology, Common Ground Kauai
John has practiced organic, ecological agriculture on Kauai for 25 years. He founded Kauai Authentic Farms in 2001, home to the Center for Regenerative Agriculture. He has taught permaculture and sustainable agriculture in Hawaii, the US mainland and in Europe. His current focus is successional multistrata agroforestry integrated with multi species grazing systems designed in accordance with the principles of deep ecology.