Endophyte infected tall fescue plants influence the grazing behavior of livestock and thus the redistribution of mineral nutrients in pasture associated with urine and dung pats (Wilkinson et al., 1989; Franzluebbers et al., 2000; Schomberg et al., 2000). Manure deposition is not a completely random process, since concentrations of nutrients occur at sites in the pasture where livestock congregate, rest, or seek shade or protection from wind and rain. Wilkinson et al. (1989) used soil K as an indicator of nutrient redistribution in response to grazing management and host-endophyte characteristics. Potassium concentrations were greatest near shade, water, and mineral-salt sources, probably as a consequence of deposition of livestock feces and urine at these sites. Soil associated with E+ tall fescue stands had greater concentrations of organic C and N than soils associated with E- tall fescue (Franzluebbers et al., 1999). This might be related to differences in soil respiration attributable to E+ plants that were somewhat less than respiration rates occurring in soils of E- tall fescue stands. The patterns of grazing behavior associated with E+ tall fescue have the potential for significant impact on nutrient management and biogeochemical processes in pastures. Detritivore populations differed in soils depending on host endophyte infection status (Omacini et al., 2007). The change in microfaunal population and resulting differences in litter decomposition would very likely have immediate and longer-term influences on nutrient availability in pastoral systems. Differences in soil organic matter concentrations would influence mineral nutrient availability and water-holding capacity, thereby influencing plant productivity and persistence.

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