An interdisciplinary online certificate and masters program in agroforestry

Paper presented at the 12th North American Agroforesty Conference, which was held June 4-9, 2011 in Athens, Georgia.In Ashton, S. F., S.W. Workman, W.G. Hubbard and D.J. Moorhead, eds. Agroforestry: A Profitable Land Use. Proceedings, 12th North American Agroforestry Conference, Athens, GA, June 4-9, 2011.Within a context of rapid technological change and shifting market conditions, the American education system is challenged with providing increased educational opportunities for students and non-traditional clients often at lower cost than in campus-based degree programs. Many educational institutions are answering this challenge by developing distance education graduate programs. These programs can provide working professionals with a chance at a graduate education, reach those disadvantaged by limited time or distance, and update the knowledge base of workers at their places of employment. Agroforestry, as a farming system that integrates crops and/or livestock with trees and shrubs, is gaining recognition as an integral component of a multifunctional working landscape. While agroforestry has been gradually gaining attention, the need for a cadre of well trained professionals in agroforestry is essential to support its continued growth. Short courses and workshops are helpful, but professionals and landowners alike across the U.S., Canada and overseas are seeking more comprehensive graduate degree or certificate programs. A web-based, asynchronous M.S. degree and/or a graduate Certificate will help to fill this void. Presently, there are no comparable comprehensive graduate programs in agroforestry elsewhere in the U.S. To meet the current and future needs of the agroforestry profession, The Center for Agroforestry at the University of Missouri is creating an online graduate certificate and masters degree program in agroforestry. The Center for Agroforestry will begin admitting students and offering online courses beginning Spring semester 2011. The certificate and masters will be fully implemented by the summer of 2013.Michael A. Gold and Shibu Jose ; The Center for Agroforestry and Dept. of Forestry University of Missouri.Includes bibliographical references

Creating the knowledge infrastructure to enhance landowner adoption of agroforestry through an agroforestry academy

Paper presented at the 13th North American Agroforesty Conference, which was held June 19-21, 2013 in Charlottetown, Prince Edward Island, Canada.In Poppy, L., Kort, J., Schroeder, B., Pollock, T., and Soolanayakanahally, R., eds. Agroforestry: Innovations in Agriculture. Proceedings, 13th North American Agroforestry Conference, Charlottetown, Prince Edward Island, Canada, June 19-21, 2013.Agroforestry offers a novel approach to land management that provides opportunities to combine productivity and profitability with environmental stewardship, resulting in healthy and sustainable agricultural systems that can be passed on to future generations. In spite of significant advances in both the science and practice of US agroforestry over the past 20 years, adoption has been limited. In the US, natural resource professionals and other educators are currently not equipped to help landowners adopt agroforestry. To advance adoption of agroforestry as a cornerstone of productive land use, a week-long agroforestry academy is being developed by a regional consortium of experts from Missouri, Iowa, Nebraska, Minnesota and Wisconsin. The academy is designed to train natural resource professionals, extension agents, and other agricultural educators who work with landowners. Advanced training will be provided on the five recognized temperate zone agroforestry practices integrated with options for bioenergy, marketing, economic, social dimensions, and environmental services. The cornerstone of the academy will be an applied planning and design exercise. Academy trainees will work in small groups to gain hands on practice in agroforestry design based on the needs of a working farm. Academy trainers and graduates will form the core of the knowledge infrastructure needed to enhance landowner adoption of agroforestry, resulting in increased sustainability of rural communities and the food and agricultural system.Michael A. Gold (1), Mihaela M. Cernusca (1) and Shibu Jose (1) ; 1. University of Missouri Center for Agroforestry, 203 ABNR Bldg., Columbia, MO 65211.Includes bibliographical references

Imperata cylindrica, an alien invasive grass, maintains control over nitrogen availability in an establishing pine forest

Abstract In a field experiment in Florida, USA, 15 Nlabeled Ammonium Sulfate was used to compare how Pinus taeda seedlings take up and use N in the presence of I. cylindrica and native vegetation using three treatments: 1) vegetation free 2) native competition, and 3) I. cylindrica competition. Imperata cylindrica competition led to smaller pine seedlings with significantly less N content in the pine foliage and roots than those in the native treatment. Competition from I. cylindrica for N contributed to the pine seedlings taking up a greater percentage of the applied fertilizer than the seedlings competing with native vegetation; however, because of their reduced growth they were less efficient in utilizing the fertilizer N. The belowground biomass of I. cylindrica on average was seven times higher than the native species. Despite its lower N concentration in foliage and roots, it retained significantly more N per hectare compared to the native vegetation. While the native species retained more N aboveground, I. cylindrica held significantly more belowground, thus invasion by this grass would lead to a shift of N pools from above to belowground. The fact that we were able to account for 81.5% of the applied fertilizer in the I. cylindrica treatment compared to 62.2% in the native treatment suggests that I. cylindrica tightly retains most of the available N on site making it a particularly good invader

Production physiology of three native ornamental shrubs intercropped in a young longleaf pine plantation

Paper presented at the 11th North American Agroforesty Conference, which was held May 31-June 3, 2009 in Columbia, Missouri.In Gold, M.A. and M.M. Hall, eds. Agroforestry Comes of Age: Putting Science into Practice. Proceedings, 11th North American Agroforestry Conference, Columbia, Mo., May 31-June 3, 2009.The production of woody floral products -- the fresh or dried stems that are used for decorative purposes -- may be an attractive option for southeastern landowners looking to generate income from small landholdings. Since many shrubs native to the understory of the longleaf pine ecosystem have market potential, one possibility is the intercropping of select species in the between-row spacing of young longleaf pine plantations. The objective of this study was to evaluate how competition affects the physiology, and thus the productivity of American beautyberry (Callicarpa americana L.), wax myrtle (Morella cerifera (L.) Small) and inkberry (Ilex glabra (L.) A.Gray) when intercropped in a longleaf pine (Pinus palustris Mill.) plantation in the southeastern United States. The effect of competition was assessed via comparisons of mortality, biomass, light transmittance, gas exchange and soil moisture between intercropping and monoculture (treeless) treatments. Overall, shrubs in the intercropping treatment performed worse than those in the monoculture, with higher mortality, and reductions in biomass of 75.5 [percent], 50.6 [percent], and 68.7 [percent] for C. americana, M. cerifera and I. glabra, respectively. Root-shoot ratios for all species were significantly higher and soil moisture during dry periods was significantly lower in the intercropping treatment. Light transmittance below the pine canopy was high (57.7 [percent]) and I. glabra was the only species that exhibited reduced photosynthesis due to shading. These results suggest that the effect of shading is minimal and belowground competition is likely the most important determinant of productivity in this system.Donald L. Hagan (1), Shibu Jose (1), Mack Thetford (2), and Kimberly Bohn (3) ; 1. School of Forest Resources & Conservation, University of Florida, Gainesville, FL USA 32611. 2. Department of Environmental Horticulture, University of Florida, Milton, FL, USA 32583. 3. School of Forest Resources & Conservation, University of Florida, Milton, FL, USA 32583.Includes bibliographical references

Competition for applied 15N fertilizer in a longelaf pine/native woody ornamental intercropping system

Paper presented at the 11th North American Agroforesty Conference, which was held May 31-June 3, 2009 in Columbia, Missouri.In Gold, M.A. and M.M. Hall, eds. Agroforestry Comes of Age: Putting Science into Practice. Proceedings, 11th North American Agroforestry Conference, Columbia, Mo., May 31-June 3, 2009.The cultivation of ornamentals to produce woody floral products -- the fresh or dried stems that are used for decorative purposes -- may be an attractive option for southeastern landowners looking to generate income from small landholdings. Since many shrubs native to the understory of the longleaf pine (Pinus palustris Mill.) ecosystem have market potential, one possibility is the intercropping of select species in the between-row spacing of young longleaf pine plantations. The objective of this study was to evaluate how interspecific competition affects the fate of 15N fertilizer when American beautyberry (Callicarpa americana L.), wax myrtle (Morella cerifera (L.) Small) and inkberry (Ilex glabra (L.) A.Gray) are intercropped with longleaf pine. Nitrogen derived from fertilizer (NDF), utilization of fertilizer N (UFN) and recovery of fertilizer N (RFNsoil) were compared between agroforestry and monoculture (treeless) treatments to assess the effect of competition. Results varied by species, with NDF being higher for C. americana foliage and lower for all M. cerifera tissues in the agroforestry treatment. No effect was observed for I. glabra. UFN was lower for all species in the agroforestry treatment. RFNsoil was higher in the agroforestry treatment for I. glabra, but no treatment effects were observed for C. americana or M. cerifera. Overall, while it is clear that interspecific competition was present in the agroforestry treatment, the inefficiency of fertilizer use suggests that nitrogen was not the most limiting resource. Management interventions, particularly those that address competition for water, will likely be critical to the success of this system.Donald L. Hagan (1), Shibu Jose (1), Mack Thetford (2), and Kimberly Bohn (3) ; 1. School of Forest Resources and Conservation, University of Florida, Gainesville, FL USA 32611. 2. Department of Environmental Horticulture, University of Florida, Milton, FL, USA 32583. 3. School of Forest Resources & Conservation, University of Florida, Milton, FL, USA 32583.Includes bibliographical references

APEX simulation : environmental benefits of agroforestry buffers on corn-soybean watersheds

Paper presented at the 13th North American Agroforesty Conference, which was held June 19-21, 2013 in Charlottetown, Prince Edward Island, Canada.In Poppy, L., Kort, J., Schroeder, B., Pollock, T., and Soolanayakanahally, R., eds. Agroforestry: Innovations in Agriculture. Proceedings, 13th North American Agroforestry Conference, Charlottetown, Prince Edward Island, Canada, June 19-21, 2013.The Agricultural Policy Environmental Extender (APEX) model has the ability to simulate the effects of vegetative filter strips on runoff and pollutant loadings from agricultural watersheds. The objectives of this study were to calibrate and validate the APEX model for three adjacent watersheds and determine optimum buffer dimensions and placement locations. ArcAPEX and APEX0604 versions were used for the simulations. The simulated corn and soybean yields were within 13% and 27% of the measured yields, respectively. The agroforestry, grass buffer, and control watershed models were calibrated (1998 to 2001) and validated (2002 to 2008) for eventbased runoff with r2 and Nash-Sutcliffe Coefficients (NSC) values of 0.7-0.8 and 0.4-0.8, respectively. The models could not be calibrated for sediment losses. The simulated grass and agroforestry buffers reduced average annual runoff by 5.2% and 4.3%, respectively. Increase of buffer widths to 5.5 m and 7.5 m were not effective. The buffers located on the backslopes were the most effective for the agroforestry watershed but this trend was not seen in the grass buffer watershed. The study provides guidance on how to parameterize APEX to simulate grass and agroforestry buffers. It contributes to the validation of APEX and will be useful to scientists in need of parameterizing the model for watersheds that include upland buffers.Anomaa Senaviratne (1, 2), Ranjith P. Udawatta (1, 2), Claire Baffaut (3), Stephen H. Anderson (1) and Shibu Jose (2) ; 1. 302 ABNR Bldg., Dept. of Soil, Environ. and Atmos. Sciences, University of Missouri, Columbia, MO 65211. 2. 203 ABNR Bldg., The Center for Agroforestry, University of Missouri, Columbia, MO 65211. 3. USDA-ARS Cropping Systems and Water Quality Research Unit, 241 Ag. Eng. Bldg., University of Missouri, Columbia, MO 65211.Includes bibliographical references

IMPACTS OF AN EXOTIC DISEASE AND VEGETATION CHANGE ON FOLIAR CALCIUM CYCLING IN APPALACHIAN FORESTS

Because of the high calcium content of its foliage, Cornus florida (flowering dogwood) has been described as a calcium "pump" that draws calcium from deeper mineral soil and enriches surface soil horizons. However, over the last two decades an exotic fungal disease (dogwood anthracnose, Discula destructiva) has decimated populations of this once-common understory species. Its loss, combined with forest stand development, could alter intra-stand calcium cycling. We used data from long-term vegetation monitoring plots to examine the ecological role of C. florida in calcium cycling and to identify changes in annual foliar calcium cycling over a 20-year period between two sampling intervals, 1977-1979 (preanthracnose) and 1995-2000 (post-anthracnose). Published equations were used to estimate foliar biomass per species for five forest types: alluvial, typic cove, acid cove, oak-hickory, and oak-pine. Calcium concentrations derived from foliage samples were used to estimate annual foliar calcium production per species for understory woody stems ( or =20 cm dbh). At a given level of soil calcium availability, C. florida foliage contained greater concentrations of calcium than three other dominant understory species (Tsuga canadensis, Acer rubrum, and Rhododendron maximum). Between 1977-1979 and 1995-2000, the annual calcium contributions of understory woody vegetation declined across all forest types, ranging from 26% in oak-pine stands to 49% in acid coves. Loss of C. florida was responsible for only 13% of this decline in oak-pine stands, but accounted for 96% of the decline in typic coves. In oak-hickory and oak-pine stands, we observed large increases in the foliar biomass of T. canadensis, a species whose calcium-poor foliage increases soil acidity. Increases in overstory foliar biomass and calcium offset understory losses in three forest types (alluvial, typic coves, and oak-pine) but not in oak-hickory and acid cove stands. Overall, calcium cycling in oak-hickory stands was more negatively affected by the loss of C. florida than the other forest types. Oak-hickory forests comprise over a third of the total forest cover in the eastern United States, and decreases in annual calcium cycling could have cascading effects on forest biota