Agroforestry Past and Present
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Working Trees for Vermont Landowners: Planting for Productivity and Land Restoration 
By Andrea Haney abhaney@uvm.edu Agroforestry Past and Present Agroforestry is a contraction of the words agriculture and forestry. This practice is a dynamic land management system that integrates trees and/or shrubs with crops and/or livestock. Not a new concept, agroforestry has been practiced for centuries around the globe, mainly in tropical and sub-tropical regions. This is not to say that our climate isn’t capable of supporting these practices. To the contrary Vermont landowners and farmers will find many species that are well suited to agroforestry practices. For those looking to diversify their lands potential, as well as improve their lives in social, economic, and environmental ways this is the ideal alternative to monoculture farming. During the early 1900’s the use of permanent tree systems in order to maximize production on arable lands was advocated by a few early farmers in the U.S. However, political and agricultural groups at the time opposed these biologically pragmatic ways deeming them too radical. The onset of the 1930’s depression along with the devastation “Dust Bowl” in the mid west forced political leaders to reconsider standard policy, and they began to support new agricultural research. Unfortunately, this innovative research ended with the post-war economic boom of the 1950’s and the introduction of fossil fuels, chemical fertilizers and the industrial technology. For a brief time during the oil crisis of the 1970’s there was renewed interest in trees and their potential role in food production. Innovators like Bill Mollison introduced concepts such as permaculture which then spurred grassroots ecological farming movements. Four main reasons for the renewal in agroforestry were:
These issues apply today but on an even greater scale, and alternative agricultural methods are again being reconsidered. Vermont landowners will find many benefits to integrating agroforestry into local farms, and even urban communities. Appropriate use of agroforestry methods enables farmers and landowners to integrate productive profitable landscapes with healthy sustainable agricultural systems. Specifically these practices will:
Planting select trees with a design approach can also add an aesthetically pleasing view to your property. This labor of love provides long lasting results that can be passed down to future generations. The following strategies are flexible tools that can be tailored based on which ones fit best with the resources you have to work with. Understanding the lay of your land, and the differences among these systems is the first step toward implementing these technologies. Windbreaks 
Windbreaks are rows of vegetation used to reduce and redirect wind. Field windbreaks improve crop yields by improving water use efficiency, and reduce wind erosion. Worldwide data selected by the USDA National Agroforestry Center shows crop yields can be improved anywhere from 5 to 45 percent. Most of these yield increases can be attributed to better water use by the protected crop. Climate stress is reduced when livestock are surrounded by vegetation. These natural buffers have been known to alter the amount of food animals consume, and reduce visual impacts. Windbreaks also provide nesting habitat for numerous bird species and small mammals. Surrounding your property with windbreaks can add value to your home, create privacy, and help conserve energy. The NAC reports that buffers planted in the correct locations can yield annual energy savings ranging from 10 to 40 percent. Key design issues are to manage for shade and wind. Riparian Forest Buffers T  his technique is similar to windbreaks but instead the trees and vegetation grow adjacent to streams, pond and wetlands. Doing so buffers these water bodies from negative impacts that originate from adjacent land-use practices, such as agriculture, urban, and industrial areas. Natural or restored streamside forests can create results in the following ways:
Silvopasture 
Silvopasture combines trees with forage and livestock production. A contraction of the words silviculture and pasture it is managed as a single integrated system. Hardwood stands can be managed for long term, high value sawlogs while the understory is managed for forage production to support livestock. Grazing by farm animals can also provide an alternative to mowing, nut and fruit orchards are ideal. Potential livestock choices include: cattle, sheep, goats, pigs, horses, turkeys, chickens. The selected livestock system must be compatible with tree, forage, environment and land use regulations. For example, poplar trees provide leaves and branches for cows. Oaks, walnuts, hazelnuts, chestnuts and hickories are suitable for pigs. Livestock farms that graze their animals could definitely take advantage of this multiuse approach. Alley Cropping 
When agricultural crops are grown in the alleys between widely spaced rows of trees thus defines alley cropping. The main difference between alley cropping and silvopasture is the absence of livestock. Annual income is provided through ground cover crops while the trees produce long term income. For example, hardwoods such as, walnut, oak, ash and pecan are favored for their high value lumber and veneer logs. Nut crops are often used as an intermediate tree product. There are many factors to consider depending on the lay of the land these include:
Forest Farming 
Forest farming is created when high value specialty crops are cultivated under the protection of the forest canopy. Forest stands can be pruned to provide the desired amount of shade. Crops such as, ginseng, shitake mushrooms and decorative ferns are often sold for medicinal, culinary and ornamental uses. This method is similar to alley cropping but in a more natural setting. Some products especially medicinal and botanicals can have tremendous economic value, while others provide lower but steady income. For example, high quality northern forest cultivated ginseng has been known to fetch $800 a pound and shitake mushrooms average a steady $10 to $12 a pound. Special Note on Non-Native Species It is important when cultivating any crop that you consider the ecological components of various exotic/non-native species. Invasive species have expansive and/or dispersive tendencies that often have long term detrimental effects on native ecosystems. When we consider the native origins of the vast majority of our cultivated crops, it becomes clear that many non-native species play a critical role in our everyday lives. That said, in order to promote sustainable stewardship through agroforestry one should be well informed of the invasive properties some non-natives carry. The following are a list of suggested species their habitats and possible uses. Keep in mind that many of these species have several suitable varieties within each family. Alnus glutinosa – Alder 
Range – Europe and North America Habitat – Wet soils in woods lakes and stream shores Primary uses – Nitrogen fixer, pioneer, soil stabilizer, timber, coppice material, charcoal windbreak, fire protection, honey, biomass, livestock fodder, fiber, insecticide, edible – seeds, flowers and seed pods
Range – Eastern North America Habitat – Rocky slopes and higher elevations Primary uses – Windbreak, edible fruits, medicine, winter bird forage, timber Robina pseudoacacia – Black locust 
Range – Eastern North America Habitat – Woods, thickets, and deep well drained calcareous soils Primary uses – Nitrogen fixer, pioneer, soil stabilizer, timber, coppice material, charcoal, windbreak, fire protection, honey biomass, livestock fodder, fiber, insecticide, edible seeds, flowers and seed pods Juglans nigra – Black walnut  
R  ange – North America
Habitat – Moist, rich, well-drained soils, bottomlands, floodplains, low mixed deciduous forest Primary uses – Edible nuts and oil, timber, insect repellent, livestock fodder, stain, wood polish
Habitat – Sterile soils, dry, gravelly, or rocky, moistly acidic soils Primary uses – Edible nuts and oil, flour, timber, coppice material, tannin, livestock fodder
Habitat – Damp rich soil, moist fields, woods, around marshes, stream and riverbanks, and fencerows Primary uses – Edible flowers, buds, and berries, wine, insect repellent, hedge, windbreak, wildlife forage
Habitat – Rich thickets, clearings, forest borders, dry or moist woodlands, hills or mountain slopes Primary uses – Edible nuts and oil, hedge, fiber, coppice material, wildlife habitat, livestock fodder
Habitat – Stream banks, old fields, woodland openings, bottomlands Primary uses – Hedge, windbreak, and livestock forage, edible fruits and leaf shoots, coppice material, wildlife habitat/forage, medicine, wine
Habitat – Stream banks, wet thickets, and moist woodlands Primary uses – Wildlife/bird forage, edible fruits, hedge, ornamental, medicine
Habitat – Floodplains, riverbanks, pastures, fencerows, abandoned fields Primary uses – Livestock fodder, windbreak, soil stabilizer, timber, coppice material, fuel, and sugar, edible seeds, pulp and pods
R Habitat – Red Mulberry: rich woods, river valleys, floodplains, lower hill slopes, and rich moist soils. White Mulberry: fencerows, roadsides, abandoned fields, woodlands Primary uses – Edible berries, juice, windbreak, livestock fodder, timber, bird forage Quercus – Oak 
Range – North American natives Habitat – White Oak: mixed deciduous forest, sandy, gravelly, loamy soils Northern Red Oak: valleys, ravines, lower and mid slopes of hill and mountains Primary uses – Edible nuts, coffee, flour, timber, firewood, windbreak, insect repellent, coppice material, livestock/wildlife fodder A  simina triloba – Paw Paw R  ange – North American native distributed throughout South Central and South Eastern U.S.
Habitat – River valleys, bottomlands, deep rich moist soils, understory Primary uses – Edible fruit, insecticide, fungicide, timber, cordage
Habitat – Woods, thickets, deep well drained calcareous soils Primary uses – Edible fruit, timber, livestock forage, shelterbelt
Habitat – Woods, hedgerows Primary uses – Edible fruit, pectin source, hedge, pollinator, timber, firewood, rootstock, livestock fodder, wildlife forage
Habitat – Praries, woodlands, pastures, roadsides, riverbanks Primary uses – Edible fruit, hedge, windbreak, soil stabilizer, bee forage, medicine, timber, fire protection
Range – North American native; widespread throughout north east and mid west Habitat – Rich woods, well drained bottomlands, dry upland slopes Primary uses – Timber, firewood, charcoal, edible: nuts, oil, sap and syrup, windbreak, livestock fodder Amelanchier – Serviceberry 
Range – North American natives; widely distributed throughout northeastern U.S.
Habitat – Tidal stream banks, rocky slopes, barrens, open woods, waste areas Primary uses – Edible berries, wildlife forage, windbreak, hedge, timber, basketry
Range – North American and European natives; widely distributed throughout U.S. Habitat – Damp fertile bottomlands, stream edges, lake rims Primary uses – Soil stabilizer, fiber, basketry, coppice material, biomass, fuel, rooting hormone, fire protection, timber, livestock fodder, medicine Bibliography Mollison, Bill (1993). Pig raising and free range forage species. Permaculture Paper #19 Yankee Permaculture The New American Farmer, Profiles of Agricultural Innovation, SARE publication, 2002, p. 83-85, Walnut Meadow Enterprises, West Virginia Working Trees for Agriculture (1999). USDA National Agroforestry Center Photos: Flickr.com, National Agroforestry Center Special Thanks Mark Krawczyk and Mike Blazewicz from Burlington Permaculture
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ange – North America
ange – North America
ange – North American and European natives
ange – North American native
ange – Eastern and North America
ange – Widely distributed throughout U.S. 
Range – Asian and European natives widespread throughout U.S.
ange – North American, Asian and European natives; widespread throughout U.S.
ange – Chinese, European and American natives; widespread throughout U.S.
