Multistrata agroforestry takes its cues from the defining feature of forests: layers. Blending an overstory of taller trees and an understory of one or more layers of crops, multistrata agroforestry maximizes both horizontal and vertical space. The blend of plants varies by region and culture, but the spectrum includes macadamia and coconut, black pepper and cardamom, pineapple and banana, shade-grown coffee and cacao, as well as rubber and timber. Home gardens are one particular approach.
By mimicking forests, multistrata systems can:
- prevent erosion and flooding,
- recharge groundwater,
- restore degraded land and soils,
- support biodiversity by providing habitat and corridors between fragmented ecosystems, and
- absorb and store carbon.
An acre of multistrata agroforestry can achieve rates of carbon sequestration comparable to those of afforestation and forest restoration, with the added benefit of producing food.
Multistrata systems are well suited to steep slopes and degraded croplands, and they can relieve pressures from natural forests by providing firewood. Farmers gain income and resilience from multiple crops growing on unique timelines. Yet, costs to establish a complex system can be high, and tending it can be more labor intensive. Incentives can help farmers overcome financial barriers and realize the multilayered benefits of multistrata agroforestry.
rates of carbon sequestration: Nair, P.K., “Climate Change Mitigation: A Low-Hanging Fruit of Agroforestry.” In Agroforestry, The Future of Global Land Use, edited by P.K.R. Nair and Dennis P. Garrity, 31-67. Dordrecht, Netherlands: Springer, 2012.; Toensmeier, Eric. The Carbon Farming Solution. White River Junction, VT: Chelsea Green Publishing, 2016.
sequestration…[vs.] natural forests: Brakas, Shushan Ghirmai, and Jens B. Aune. “Biomass and Carbon Accumulation in Land Use Systems of Claveria, the Philippines.” In Carbon Sequestration Potential of Agroforestry Systems: Opportunities and Challenges, edited by B. M. Kumar and P.K.R. Nair, 163-175. Dordrecht, Netherlands: Springer, 2011.
250 million acres of multistrata agroforestry: Nair, “Agroforestry.”
Cacao…20 million acres: Zomer, Robert, et al. Trees on Farm: Analysis of Global Extent and Geographic Patterns of Agroforestry. Nairobi: World Agroforestry Centre, 2009.
Shade-grown coffee…15 million acres: Jha, Shalene, et al. “Shade Coffee: Update on a Disappearing Refuge for Biodiversity.” BioScience 64, no. 5 (2014): 416-28.
Full-sun coffee farms…[vs.] shade farms: Clay, Jason. World Agriculture and the Environment: A Commodity-by-Commodity Guide to Impacts and Practices. Washington, D.C.: Island Press, 2004; Huizen, Jennifer. “How Green Is Your Coffee?” Scientific American. October 1, 2014.
Home gardens…13,000 BC: Nair, P.K.R., and B.M. Kumar. “Introduction.” In Tropical Homegardens: A Time-Tested Example of Sustainable Agroforestry, edited by B. Mohan Kumar and P.K. Ramachandran Nair, 1-10. Dordrecht, Netherlands: Springer, 2006.
The Ramayana and The Mahabharata…Ashok Vatika: Puri, S., and P. K. R. Nair. “Agroforestry Research for Development in India: 25 years of Experiences of a National Program.” In New Vistas in Agroforestry, 437-452. Dordrecht, Netherlands: Springer, 2004.
[use in] Indonesia…India: Nair and Kumar, “Introduction.”
“the epitome of sustainability”: Nair, P.K.R. “Whither Homegardens?” In Tropical Homegardens: A Time-Tested Example of Sustainable Agroforestry, edited by B. Mohan Kumar and P.K. Ramachandran Nair, 355-370. Dordrecht, Netherlands: Springer, 2006.
agroforestry can prevent deforestation: Dixon, R. K. “Agroforestry Systems: Sources of Sinks of Greenhouse Gases?” Agroforestry Systems 31, no. 2 (1995): 99-116; Montagnini, F., and P. K. R. Nair. “Carbon Sequestration: An Underexploited Environmental Benefit of Agroforestry Systems.” Agroforestry Systems 1, no. 61-62 (2004): 281-295.
calories of energy [per] calorie of food: Manner, Harley. “Sustainable Traditional Agricultural Systems of the Pacific Islands.” In Agroforestry Landscapes for Pacific Islands: Creating Abundant and Resilient Food Systems, edited by Craig Elevich. Holualoa, HI: Permanent Agricultural Resources, 2015.
Correction: [A]n acre of multistrata agroforestry can achieve rates of carbon sequestration that are comparable to those of afforestation and forest restoration—2.8 tons per acre per year, on average.
Correction: One study suggests every acre of agroforestry can prevent deforestation of five to twenty forest acres.