Nearly two-thirds of Alabama (about 22 million acres) is forestland, 75% of which is owned by non-industrial private landowners. Thus, family forests make up the majority of forest ownerships in Alabama (Schelhas and Zabawa, 2005). However, many landowners view their forested land as a source of returns from timber rather than as a source of revenue from multiple land use systems that incorporate harvesting and marketing non-timber forest products, particularly forest medicinal plants in a system called the forest farming, alley cropping, silvopasture, and other possible agroforestry practices.
Agroforestry is a sustainable land-use system that involves the intentional integration and management of trees, crops, and/or livestock in a single management unit. Agroforestry systems involve seven distinctly different, purpose-driven practices with components that are site-specific and closely inter-related. These practices have been succinctly described with illustrations and examples in Agroforestry Training Handbook (Karki, 2015). Alley cropping is defined as an agroforestry practice in which alleys between large fruit, nut, or timber trees are cropped with vegetables, row crops, forages, herbs, flower/ornamental plants, or small fruit shrubs to increase regular, short-term income.
Alabama A&M University and Tuskegee University are working together with funding support from USDA/NIFA Agriculture and Food Research Initiative (AFRI). Alley cropping of market-ready specialty vegetables such as: i) Chinese eggplant (Solanum melongena), ii) Indian eggplant, iii) bell peppers (Capsicum species), iv) bitter melon (Momordica charantia), v) poblano/ancho peppers (Capsicum annuum var. annuum), and vi) roselle (Hibiscus sabdariffa) will be evaluated in two different tree production systems: pecan (Carya illinoinensis) trees and loblolly pines (Pinus taeda). Specialty vegetable crops selected for evaluation in this project are already familiar with ethnic and mainstream consumers, and readily supplied through common grocery stores, farmers markets, and ethnic stores, at least in Alabama. This project will explore the detailed production management of these vegetables in association with tree production, and asses the environmental and economic benefits of this production system. Each fall, a winter cover crop - mixture of crimson clover (Trifolium incarnatum) and rye (Secale cereale) will be planted soon after the vegetables are harvested. The rationale for evaluating these vegetables with loblolly pine and pecan tree-based agroforestry systems is to determine relative economic values of long-term returns from each system. Additionally, differences in benefits associated with different tree architecture will be determined, particularly in terms of ecosystem services. The spread out canopy of pecan tree compared to vertical canopy of loblolly pines are expected to have significant effects on microclimate, and thus yields of alley crops. After five years of intensive data generation from this study, pruning might be resorted to ensure adequate light transmission through the canopy to the alley crops. Because trees grow slowly and it takes a long time to generate income from such practices compared to annual crops, there is a plan to extend the duration of the study beyond five years based on these results, so that long-term effects of trees on annual crop yields and soil quality can be evaluated.
The relative changes in soil quality variables such as soil physical (bulk density, infiltration, soil water retention, soil moisture profiles) and chemical (soil pH, CEC, soil organic matter, and nutrient profiles) properties associated with vegetable alley cropping will be determined. Relative economic benefits of cover crop-based alley cropping of specialty vegetables will be computed and outreach events (field days, training sessions) for farmers, landowners, extension professionals, and resource managers will be conducted. Several landowners/farmers, extension service professionals, foresters, and graduate and undergraduate students are expected to gain knowledge and skills on developing and managing alley cropping systems from this project.
Karki, U. (Ed.). 2015. Sustainable agroforestry practices in the Southeastern Region: training handbook. Cooperative Extension, College of Agriculture, Environment and Nutrition Sciences, Tuskegee University, Publication No. TUAG1015-01. Available Online: http://www.tuskegee.edu/sites/www/Uploads/Users/732/Files/tucep/Agroforestry/Agroforestry_Handbook.pdf
Schelhas, John; Zabawa, Robert. 2005. Model forest landowners in Alabama: are they different from typical landowners?. In: Proceedings of the 11th International Symposium on Society and Resource Management, Ostersund, Sweden. P. 48.