Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 28, 2005
Publication Date: October 25, 2005
Citation: Ritchie, J.C., Reeves III, J.B., Krizek, D.T., Foy, C.D. 2006. Fiber composition of eastern gamagrass forage grown on a degraded, acid soil. Field Crops Research. 97:176-181. Interpretive Summary: With increasing emphasis on sustainable agriculture, there is renwed interest in the use of native plants (eastern gamagrass) as alternative crops for food, fiber, and soil improvement. Fiber composition and digestibility of eastern gamagrass grown on a degraded, acid soil was determine to evaluate forage quality. Time of harvest generally had a greater effect on forage composition than did site location. Plants were generally high in fiber as reflected by high NDF and ADF contents.Crude protein and digestibility, while not as high as found in some forages, were good and similar to composition reported for other forages. In general, forage quality as indicated by lower fiber (NDF, ADF, lignin) and higher digestibility and crude protein increased as soil condition degraded and enviromental stress (deficit rainfall) increased. This study demonstrated that eastern gamagrass produced good quality forage under marginal soil and enviromental conditions. As a warm season forgae, eastern gamagrass can provide good quality forage in the warm summer months when the cool season forage production is limited.
Technical Abstract: With increasing emphasis on sustainable agriculture, there is renewed interest in the use of native plants as alternative crops for food, fiber, and soil improvement. Eastern gamagrass [Tripsacum dactyloides (L.) L.] is a native, warm-season, perennial bunch of grass found in the eastern United States. It has many attributes making it useful for agricultural use as a forgae and cover crop. The objective of this research was to investigate the fiber composition and digestibility of eastern gamagrass grown on a degraded, acid soil at the Beltsville Agricultural Research Center, Beltsville, MD. Eastern gamagrass forage smaples were harvested at the heading stage in July of 1997, 1998, and 1999 from a degraded hillside with increasing soil acidity and decreasing surface soil depth from the bottom to top of the hill slope and analyzed for fiber, crude protein, and insitu digestibility. Year of harvest had the greatest effect on forage composition. Fiber composition was also related to slope position and soil acidity. Plants were generally high in fiber as reflected by high neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents, but were not particularly high in lignin. Crude protein (6 to 11%) and digestibility were good and comparable to values reported for eastern gamagrass in other studies and comparable to otherforage species. Eastern gamagrass produced exceptional yields of forage and has crude protein content and palatability comparable to values for high quality alfalfa hay. Thus the overall picture indicates that eastern gamagrass is comparable in forage composition and digestibility to many hay forages in use today even when grown on an degraded acid soil.