Abstract:
Within the tall grass prairie community a number ofshrubby invaders are encroaching on the established vegetation. One of these invaders is buckbrush, Symphoricarpos orbiculatus. This study was undertaken to determine if allelopathic inhibition was a factor in that invasion. The site selected for the research was an established prairie community on the Ross Natural History Reservation, northwest of Emporia in Lyon County, Kansas. Over a four year period, observations revealed that one established stand of s. orbiculatus increased an average of 0.636 m/year in diameter. Extracts of the root, foliage and fruit of S. orbiculatus were prepared for use in seed germination, seedling growth and development and chromatographic portions of the study. The major members of the tall grass prairie (Andropogon gerardi, Andropogon scoparius, Panicum virgatum and Sorghastrum natans) were used as the test species in the germination and development tests. The effects of these extracts established that an inhibition was taking place. a. scoparius, p. virgatum and s. nutans showed significant decreases in germination and development. The species showing the least susceptibility to the inhibition was a. gerardi. Chromatograms were used to verify the presence of potentially alleopathic phenolic compounds in the S. orbiculatus extracts.
