Development of agroforest systems for bioenergy crop production and ecosystem services in the lower Mississippi Alluvial Valley

Project Overview

Project Type: Research and Education
Funds awarded in 2009: $180,000.00
Projected End Date: 12/31/2013
Region: Southern
State: Louisiana
Principal Investigator:
Dr. Hal Liechty
School of Forest Resources, University of Arkansas

Annual Reports


  • Additional Plants: native plants, trees


  • Crop Production: agroforestry, forestry, intercropping
  • Education and Training: demonstration, extension, workshop
  • Energy: bioenergy and biofuels
  • Farm Business Management: budgets/cost and returns
  • Natural Resources/Environment: carbon sequestration, biodiversity, habitat enhancement
  • Production Systems: agroecosystems
  • Soil Management: soil analysis, nutrient mineralization, soil chemistry, organic matter, soil quality/health

    Proposal abstract:

    Our goal is to develop economically and ecologically sustainable agroforest systems for producing dedicatedcellulosic bioenergy crops on marginal agricultural land in the Lower Mississippi Alluvial Valley (LMAV). This goal is consistent with the desire to “expand the focus in bioenergy beyond corn-and soybean-based ethanol and biodiesel” as indicated in the Southern SARE Position Paper, “Addressing the Development of a Sustainable Bioenergy/Energy Future”. The proposed project addresses two themes in this position paper: “Alternative Biomass Feed Stock Systems” and “Environmental Impact of Bioenergy Production”. To accomplish our goal, we are currently establishing agroforest systems composed of alley cropped mixtures of cottonwood trees (Populus deltoides L.) and switchgrass (Panicum virgatum L.) at three sites which have soils with low potentials for growing conventional row crops. These sites are located along the LMAV from northeast Arkansas through northeast Louisiana and will be a focus of long-term (10+ years) bioenergy research. Cottonwood and switchgrass are adapted to a wide range of soil and site qualities; produce high yields of cellulose with minimal additions of nutrients, water, or pesticide; and provide important ecosystem services such as soil carbon sequestration, nutrient retention, and wildlife habitat. Development of agroforest systems with the flexibility of growing alleys of switchgrass between rows of cottonwood trees in a single field would expand the ability of small and mid-size landowners and farmers to produce a diversity of economic and social outputs from their landholdings. Our SARE proposal focuses on the economic and environmental assessment of these agroforest systems as well as the delivery of information to stakeholders concerning the applicability of cottonwood/switchgrass agroforests for producing bioenergy feedstocks. To assess these systems we will: (1) measure the biomass and potential biofuel yields from these systems, (2) determine the investment potential of these systems by monitoring management costs and potential biofuel revenues, (3) determine the potential of these agroforests to sequester soil carbon, (4) quantify the impact of different cottonwood/switchgrass compositions on water quality by monitoring nitrogen concentrations in water draining from these systems, and (5) evaluate the influence of these agroforest systems on wildlife by measuring habitat characteristics and monitoring small mammal populations. The SARE project will provide us with an assessment of establishment and early development of these systems. Using this data, we will model cottonwood growth to provide long-term estimates of yields and economic returns from these systems. To focus our research efforts and facilitate information transfer to farmers and other landowners, we have organized stakeholder advisory committees to help guide research efforts and to delineate current and future information programs needed by the citizens of the LMAV concerning these bioenergy crops and agroforest systems. We will organize field days to demonstrate appropriate harvesting and biomass-fuel conversion technologies, develop resources and training for county agents, and create printed as well as web-based materials to educate landowners, government officials and natural resource management professionals on the use of these agroforest systems for bioenergy production and environmental conservation.

    Project objectives from proposal:

    The objectives of this project are to:

    1. Quantify biomass production, potential bioenergy (ethanol, syndiesel, etc.) yields, and economics of agroforest systems with a variety of cottonwood and switchgrass compositions.

    2. Quantify ecosystem services (carbon sequestration, nitrogen retention, wildlife habitat, and biodiversity)provided by agroforest systems with a variety of relative cottonwood and switchgrass compositions.

    3. Provide information to farmers, bioenergy industry professionals, county agents, natural resource managers, and regional public officials on the production potential, financial viability, and ecological impacts of cottonwood/switchgrass agroforest biofeedstock systems; demonstrate establishment, harvesting, and bioenergy conversion technologies appropriate to these agroforest systems; and establish a stakeholder research and outreach steering committee to direct current and future project activities concerning these cropping systems.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.