SGS-LTER Bouteloua gracilis Removal Experiment Vegetation Point of Intercept (Cover) Data on the Central Plains Experimental Range, Nunn, Colorado USA 1997-2005, ARS Study Number 155

This data package was produced by researchers working on the Shortgrass Steppe Long
Term Ecological Research (SGS-LTER) Project, administered at Colorado State University.
Long-term datasets and background information (proposals, reports, photographs, etc.) on
the SGS-LTER project are contained in a comprehensive project collection within the
Digital Collections of Colorado ( Six sites approximately 6 km apart were selected at the Central Plains Experimental Range in 1997.
Within each site, there was a pair of adjacent ungrazed and moderately summer grazed (40-60% removal of
annual aboveground production by cattle) locations. Grazed locations had been grazed from 1939 to present
and ungrazed locations had been protected from 1991 to present by the establishment of exclosures.
Within grazed and ungrazed locations, all tillers and root crowns of B. gracilis were removed from two
treatment plots (3 m x 3 m) with all other vegetation undisturbed. Two control plots were established
adjacent to the treatment plots. Plant density was measured annually by species in a fixed 1m x 1m quadrat
in the center of treatment and control plots. For clonal species, an individual plant was defined as a
group of tillers connected by a crown (Coffin and Lauenroth 1988, Fair et al. 1999). Seedlings were
counted as separate individuals. In the same quadrat, basal cover by species, bare soil, and litter
were estimated annually using a point frame. A total of 40 points were read from four locations halfway
between the center point and corners of the 1m x 1m quadrat. Density was measured from 1998 to 2005 and
cover from 1997 to 2006. All measurements were taken in late June/early July.