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Forage producers need more efficient, less risky, and cost-effective strategies for replacing existing stands of toxic endophyte infected (E+) grass. This study addressed the efficacy of E+ tall fescue [Lolium arundinaceum (Schreb.) Darbysh. = Schedonorus arundinaceus (Schreb.) Dumort =] control using available herbicides, differing herbicide application timings, and weed control techniques and assessed the survival of E+ seed during the summer after it was produced. Two small-plot experiments near Blairsville and Watkinsville, GA, evaluated herbicide chemistry and compared different application protocols for glyphosate at different time intervals (0, 2, 4, and 6 wk) to the use of a summer annual smother crop between split applications of glyphosate. Glyphosate allowed fewer E+ escapes than the other herbicides tested. Split applications of glyphosate at 6 wk before planting and again 1 d before planting resulted in successful eradication of the E+ tall fescue stand, fewer weeds, and a successfully established stand of nontoxic endophyte infected (NT) tall fescue. In a separate experiment at Blairsville and Watkinsville, 7.4 and 8.5 seeds per 100 seeds produced, respectively, were found to be germinable and with viable endophyte despite exposure to ambient conditions on the canopy floor in 2004. Thus, spring suppression of E+ tall fescue seedheads could reduce the risk of remnant toxic E+ seed. In field-scale tests of the developed protocol [spring suppression of seedheads and a split application of glyphosate (6-wk interval) before an autumn planting], E+ tall fescue stands were destroyed successfully and renovated with a NT tall fescue with a range of E+ escapes being only 0.5 to 2.5%. [ABSTRACT FROM AUTHOR]

The article discusses a study to evaluate water quality in two streams flowing through tall fescue pastures with different shade distribution, and to evaluate the effects of alternative water sources on stream water quality. A secondary, supporting objective was to determine the amount of time spent by cattle in the riparian areas of these pastures. The streams used in this study flowed through two pastures located at the Central Research and Education Center of the University of Georgia, Georgia. Portable samplers were installed where the stream entered and exited each pasture. Monitoring of water quality during storm events took place with and without water troughs available. When water troughs were not available, an electric fence around the troughs prevented cattle access to them. At the onset of the project, the intention was to evaluate water quality for 1 year with water troughs available, then close the water troughs in March 2002 and evaluate water quality without water troughs for one additional year. Due to the nature of this study and the distribution data, parametric statistical procedures were not applicable, therefore, the analysis was performed with nonparametric methods.

Cattle use of riparian areas may lead to stream water contamination with nutrients, pathogens, and sediments. Providing alternative water away from the stream may reduce the amount of time cattle spend near streams and therefore reduce contamination. We conducted this study to 1) evaluate the effect of providing water troughs outside of the riparian zones on the amount of time cattle spend in riparian zones, and 2) evaluate if environmental factors such as temperature and humidity affect the impact of water trough availability on the amount of time cattle spend within riparian and nonriparian locations. Global positioning system (GPS) collars were used to document cow locations every 5 min in 2 mixed tall fescue/common bermuda-grass pastures of the Georgia Piedmont in the United States. We found that when the temperature and humidity index (THI) ranged between 62 and 72, providing cattle with water troughs outside of riparian zones tended to decrease time cattle spent in riparian zones by 63% (52 min x d(-1); P = 0.11). When THI ranged between 72 and 84, nonriparian water availability did not have a significant impact on the amount of time cattle spent in the riparian zone or in riparian shade. These results suggest that water troughs placed away from unfenced streams may improve water quality by reducing the amount of time cattle spend in riparian zones when environmental conditions as evaluated by THI are not stressful.