Southern Region Sustainable Agriculture Research and Education

From garlic juice to combat goat parasites to biofuel made from sweet sorghum and airblown cotton gin waste replacing black plastic mulch, if this year's winners have a common theme it's that they investigate low-tech approaches to solve persistent problems. As always, no proposal is perfect; they all have strengths as well as areas they could make stronger.

It always helps if a proposal addresses more than one problem such as OS07-033, which uses very high-value indigeneous trees as the perennial crop for shading coffee. The ecological value of shade-grown coffee is enhanced even more by the low-maintenance requirements of indigenous trees. The economics are beneficial for the farmer because the shade trees serve as a profitable second crop. Reviewers thought OS07-034 was worth funding to find out if the seemingly simple idea of using a hydroseeder to blow drifts of cotton gin waste and other agricultural by-products across fields could replace black plastic mulch with all its labor costs and environmental concerns. Solid planning, a broad base of researchers, a conservative budget and wilt-fighting potential for crops beyond watermelon were mentioned positively in reviews of OS07-035 .Effective collaboration between unitversities, researchers and farmers helped the turkey tasting project OS07-036 get noticed. A double cover crop of brassicas and vetch proposed by project OS07-037intrigued reviewers for its potential to address hardpan and weeds in more than one cash crop. Sometimes a proposal gains credibility because a producer brought the problem or a solution to a researcher. That's how the idea came about for project OS07-038 which will examine the feasibility of a farm-based sorghum-biofuel production system. Sound planning to address a common and growing problem brought the herbal solutions proposed in OS0-039 to the attention of reviewers.

Keep up with these projects by reading progress reports which are posted online each April. Just click on Projects and follow the link to the data base.

OS07-033	Precious Indigenous Woods For Coffee Shade, $14,967
OS07-034	Hydroseeded mulch as an alternative to plastic mulch films, $14,000
OS07-035	On-Farm Use of a Hybrid Vetch Cover Crop to Reduce Fusarium Wilt in Seedless Watermelon, $9,900
OS07-036	Sensory Evaluation of Alternative Turkey Genotypes, $14,962
OS07-037	Allelopathic potential of a biculture cover cropping system utilizing Fabaceae and Brassicaceae cover crops, $12,840
OS07-038	On-Farm Biofuel Production from Sweet Sorghum Juice, $14,898
OS0-039	The Use of Controlled Grazing and two Herbal Treatments to Prevent Parasitism in Sheep and Goats, $14,967

OS07-033 Precious Indigenous Woods For Coffee Shade, $14,967

We propose to combine coffee with non-traditional precious wood trees to provide for a sustainable coffee producing area. Precious wood trees have never been planted for shade in Puerto Rico's coffee region. We want to look more at native precious woods because it will have more economic impact for farmers. These species are also much sought after by the local artesian industry for furniture, craft items, boats, decks, cabinets, yachts among other wood products.

This project seeks to research native precious wood species for suitability to alley cropping systems to produce higher elevation gourmet coffee. Some of these trees such as Manilkara bidentata, Buchenavia tetraphylla and Bucida buceras L., are deep rooted and well adapted to resisting hurricane and high wind problems.

Besides higher returns, precious woods provide shade on coffee crops and other multiple benefits on natural resources. The planting of these species would assist in bio-diversity concerns on the island. They will protect soil from erosion, and improve water quality and quantity of reservoirs in the coffee region. Tree species such as Thespesia grandiflora, Hibiscus elatus Sw. and Ocotea moschata are excellent for the establishment riparian forest buffers. The entire coffee region (75,000 acres) has been programmed to be part of the ecological corridor of Puerto Rico. This project is a great opportunity to preserve native precious woods. Several of these species are threatened species.

Hydro-seeders are used extensively in landscaping and erosion control practices spread seed and mulch across landscapes. These machines can be adjusted to spread materials with a variety of consistencies. Mr. Rawlings wants to test agricultural bi-products alone, in combinations, or in a processed form with the objective of identifying an organic ground cover that provides many of the moisture repellency, heat absorption, and weed control advantages of plastic film mulches. Specifically, he would like to test agricultural waste products such as cotton gin trash, compost, crushed peanut hulls, and crushed pecan hulls as well as bi-products from the production of biofuels as potential mulch materials. In addition to testing raw waste materials, Mr. Rawlings is interested in working with researchers to identify potential combinations or processed forms of waste materials that could be mechanically spread across the surface of planting beds using a hydro seeding machine. Having raised livestock, Mr. Rawlings suggests that hydro seeded applications of organic materials could potentially replace plastic coverings over bunker silos.

Benefits Mr. Rawlings seeks to obtain by identifying a mechanically applied mulch product include not having to remove plastic mulch from his fields, increased soil organic matter, improved nutrient cycling, and enhanced physical, chemical, and biological quality of his soil. He is also interested in working with other farmers to help them obtain similar benefits on their land.

OS07-035 On-Farm Use of a Hybrid Vetch Cover Crop to Reduce Fusarium Wilt in Seedless Watermelon, $9,900

A new management tactic for Fusarium wilt is the production of watermelon following a fall-planted hairy vetch cover crop that is killed in the spring and turned into the soil as a green manure (Zhou and Everts 2004). Incorporating hairy vetch (Vicia villosa) in the spring prior to transplanting watermelon reduced incidence of Fusarium wilt and increased yields in Maryland compared with fallow (Zhou and Everts, 2004). Average reduction in Fusarium wilt was 45%, which was as good as control with methyl bromide or Telone C-35 fumigation. Watermelon yields after a hairy vetch cover crop increased from 35% to 65% compared to the control treatment, again, as good as the fumigants. In addition, hairy vetch was effective against both race 1 and 2 of FON.

While hairy vetch winter cover crops have consistently reduced Fusarium wilt in many research trials in Maryland, hairy vetch has not been widely adopted in the mid-Atlantic region. One problem is that hairy vetch is a good host of Southern root-knot nematode (Meloidogyne incognita), the predominant root-knot species in the South. However, a hybrid cultivar of common vetch 'Cahaba White' (V. sativa x V. cordata) is a poor host and so is resistant to Southern root knot nematode (Gallaher et al., 1988; Timper et al., 2006) and will be tested for suppression of Fusarium wilt in this project.

Biomass of common vetch in a previous study from Georgia, 1.9 tons/acre (Hargrove, 1986), was similar to the biomass of hairy vetch produced in Maryland, 2.1 tons/acre (Zhou and Everts, 2004). Thus, it appears very likely that vetch will grow as well in the South as hairy vetch has in the mid-Atlantic region.

The University of Arkansas (UA) will assemble an integrated team for on-farm research to investigate the meat quality and sensory attributes of heritage turkeys. The UA Dept. of Poultry Science is experienced in meat quality and sensory research of poultry products, including specialty products. The UA has received awards to investigate the sensory qualities of slow-growing chicken genotypes in free-range production (Owens, 2003; Owens, 2004), as well as for organic production (Emmert, 2004). The UA Food Science and Engineering Department has a state-of-the-art sensory facility (www.uark.edu/ua/sensory/index.htm). The facility regularly conducts consumer evaluations and has a 15-member trained panel, which is one of the few panels in the U.S. trained to work with poultry products.

Mike Walters, manager of Walters Hatchery, is a local heritage turkey producer in Stilwell, Oklahoma. He is well-known in the sustainable agriculture community for his work in conserving turkey genetics. Walters Hatchery maintains breeding flocks of some of the improved lines of heritage turkeys. They raise eight types of heritage turkey which can be viewed at the website www.waltershatchery.com. The operation, as a participant in the National Poultry Improvement Plan, has documented clean heath status. The proposed research is based an on-farm collaboration with Mike Walters and his family. They raise turkeys with access to the outdoors as many small free-range farmers do across the U.S. The birds will be processed at the UA Pilot Processing Plant, and the meat quality and sensory evaluations will be conducted in laboratories and sensory facilities at the UA.

An outreach plan will ensure the results of this trial reach the sustainable agriculture community and others interested in agricultural enterprises that boost small farmer income while maintaining environment resources and addressing societal concer

OS07-037 Allelopathic potential of a biculture cover cropping system utilizing Fabaceae and Brassicaceae cover crops, $12,840

Fabacaceae (legume) and Brassicaceae are two families of cover crops that are often recommended in a sustainable production system because of their unique properties and benefits on the soil. The use of allelopathic legume cover crops is of great interest because of their ability to fix nitrogen (Hill et al 2006). Several studies have shown the allelopathic potential of legume cover crops (Njoujio & Mennan 2005; Teasdale 1996; Hutchinson & McGiffen 2000). One such group of legume cover crops that have shown strong allelopathic capabilities is the vetches (Njouajio & Mennan 2005, White et al 1989; Hill et al 2006). Vetches, which include hairy vetch, purple vetch, and lana vetch, perform well over a wide range of soils, can fix over 100 pounds of nitrogen per acre and release about half of it to the following cash crop (Schonbeck & Morse 2006). They also make soil phosphorus more available and provide habitats for beneficial insects.

Cover crops in the brassica family, which includes daikon, oilseed, and fodder radishes, are often chosen as cover crops because they are deep rooted crops that can help open subsoil hardpan (Schonbeck & Morse 2006). This characteristic is especially important in areas where traditional tillage has left a layer of hard soil just under the disturbed soil area. Other advantages include conservation of soluble nitrogen and rapid canopy closure to help prevent weed seed germination (Schonbeck & Morse 2006). These cover crops are also known to have strongly allelopathic root exudates, which can leave behind a weed-free seedbed after winterkill.

Planting a brassica and legume cover crop as a biculture could be very beneficial. In areas where traditional agricultural practices, such as mold-board plowing, have left a hardpan under the soil, the brassica cover crop could help break-up this layer. Incorporating a legume cover crop, that will help fix nitrogen, could prove to be very beneficial, especially in areas where the soil contains very low organic matter. Weed suppression could also be increased by incorporating the two families, instead of planting a monoculture cover crop system. However, it is important to understand how these crops will not only affect one another, but the cash crops that would follow behind this system. If increased weed suppression occurred from the biculture system, it stands to reason that cash crops could be negatively affected, as well. It is necessary to conduct field studies examining this system before it is recommended to growers. Therefore, the objectives of this study are to determine: 1. compatibility of a brassica and legume cover crop in a biculture production system, 2. weed suppression when brassica and legume cover crops are planted as a mono-and biculture, and 3. effects on a cash crop when brassica and legume cover crops are planted as a mono- and biculture.

Sweet sorghum is a sugar crop, similar to sugar cane and sugar beets, that may show promise as a source of sugar for ethanol fermentation (Nathan, 1978). It is an annual crop in the grass family. It is noted for its high photosynthetic efficiency, adaptability to temperate regions and drought resistance (Worley et al., 1992; Gnansounou et al., 2005; Martini et al., 2006). The pith or stalks can be mechanically pressed to release a sugar juice (15-22 °Brix) that can be filtered and directly fermented by yeasts. The resulting ethanol can be separated through subsequent centrifugation and distillation processes. The primary advantage of sweet sorghum over starch and lignocellulsic sources is the reduced processing steps and inputs required for complete conversion, which may reveal improved economic benefits over corn feedstocks (Worley et al., 1992). Challenges in using sweet sorghum juice include the harvest time that is limited to 3-4 months per year and maintenance of juice stability. A number of reports suggest that juice extraction should occur soon after harvest and processing needs to take place immediately (Gnansounou et al., 2005; Kundiyana et al., 2006). In effort to obviate some of the issues with juice transportation, storage and stability, this proposal aims at providing growers with the opportunity to generate their own fuel ethanol. Efforts have been made to achieve in-field ethanol production facilities with some success, yet the design has not been fully developed and implemented (Kundiyana et al., 2006).

With some technical assistance, NC farmers have a great opportunity to benefit from the growing need for biofuels and other biobased products that can be generated through bioprocessing of farm-produced biomass. Recently, a local grower from Nash County, North Carolina realized this potential and sought our assistance in configuring a production system that would process sweet sorghum into juice and yield ethanol. His vision was to design a process that could assist farmers in raising their own fuel from the farm and support the cultivation of a sustainable, wholly value added crop. Thus, we identified a need to define a working process for on-farm conversion of sweet sorghum at an intermediate level as a step toward enhancing economic development.

This proposed work will assist the development of an on-farm sorghum-to-ethanol production system for the purpose of evaluating the techno/economic potential and the level of grower interest in producing biofuels on farm. Preliminary small-scale field studies were conducted during October 2006 using the sweet sorghum crop that Mr. Gerald Sykes (Nash County) had grown and offered for our use. The whole stalks were pressed with fodder removed to improve juice quality and yield (Worley et al., 1992). The juice was filtered (for removal of bacterial contaminants) and stored at three conditions (fresh, frozen, concentrated syrup (~30o Brix)). The completed fermentations indicated that the Red Star® yeast can effectively use non-sterile sweet sorghum juice for conversion to ethanol within five days at ambient temperature.

OS07-039 The Use of Controlled Grazing and two Herbal Treatments to Prevent Parasitism in Sheep and Goats, $14,967

Controlled or management intensive grazing provides a good management strategy for preventing parasitism in many sheep and goats. Grazing forage at a height that provides optimal nutrition also keeps livestock from ingesting high levels of parasitic larvae. Weather plays a role and rain events need to be monitored to determine rotations of livestock to prevent grazing pastures with high larval numbers due to moist conditions. Certain pasture plants have anthelmintic properties. How often and for how long livestock need to graze on these plants remains to be fully determined. Selecting for animals that exhibit a high level of resilience, in other words, being able to produce and perform even with internal parasites, has to be carefully done. Mixed species grazing helps to break parasite life cycles of both livestock species. Some herbal remedies appear to have an effect but dosages and frequencies of treatment are unknown.

This project will address all of the above approaches. The sheep flock at Heifer Ranch has been rotationally grazed using controlled grazing techniques for three years. The rotations have been based on forage height, animals' nutritional needs and presumed parasitic larval pasture contamination. Cattle have been grazed after sheep to help break the parasite life cycles. Chicory (Cichorium intybus) has been planted in one pasture as an anthelmintic treatment though grazing. A garlic juice preparation has been given to predetermined group of sheep for the purpose of determining changes in fecal egg counts and weight gains. This same garlic juice preparation has been given to sheep that have shown signs of parasitism, based on fecal egg counts, FAMACHA eye test scores and other clinical signs. Papaya seeds have also been given as a treatment following garlic juice treatment. This treatment has shown some astonishing results. Rainfall data have been recorded and plotted over the last 3 years. Each year has been vastly different but we have not changed our pasture rotations due to rainfall.

Our goal is to have no clinical cases of parasitism in our sheep. But since that is very difficult to achieve given our climate we want to have some natural, non-chemical anthelmintics we know will work. Because of our success with our grazing management and the results of the garlic and papaya, we feel that these approaches can provide sheep and goat producers with some effective control measures.

2007 On-Farm Research Projects

OS07-033 Precious Indigenous Woods For Coffee Shade, $14,967

The content and opinions expressed on this Web page do not necessarily reflect the views of,
nor are they endorsed by, the University of Georgia or the University System of Georgia.

2007 On-Farm Research Projects

OS07-033 Precious Indigenous Woods For Coffee Shade, $14,967

The content and opinions expressed on this Web page do not necessarily reflect the views of, nor are they endorsed by, the University of Georgia or the University System of Georgia.

The content and opinions expressed on this Web page do not necessarily reflect the views of,
nor are they endorsed by, the University of Georgia or the University System of Georgia.