Precipitation, Soils and Herbage Production on Southeast Wyoming Range Sites

Abstract

Herbage production and precipitation were determined at 13 locations in 483 ha of mixed grass range 1975-1979; production was determined at all locations 1982-1983, but precipitation was measured only at the main weather station. Vegetation and herbage production were more uniform on sites with similar subsoil than on sites with similar surface soil, the usual basis for site classification. Within any year, herbage production on similar sites was not correlated with spatial distribution of precipitation. Across years 1975-1979 and 1982-1983, herbage production on sites with sandy subsoil was correlated with March-April weather station precipitation (r2=0.866**) and March-April plus May-August precipitation (R2=0.95**). Herbage production on sites with loamy subsoil was not significantly correlated with precipitation in March-April (r2=0.32) or any other period.