Published source details
Potvin M.A. & Harrison A.T (1984) Vegetation and litter changes of a Nebraska Sandhills prairie protected from grazing. Journal of Range Management, 37, 55-58
The semi-arid Sandhills prairie region of Nebraska comprises one of the largest extant prairie areas left unploughed in the USA. It is defined as a ‘mixed’ prairie (supporting unique ‘tall’ and ‘short’ grass, and sand tolerant communities). Large areas have been subject to long-term overgrazing by livestock. On Arapaho Prairie (536 ha), a Sandhills prairie site, vegetation changes were recorded during the first 4-years following cessation of intense cattle grazing.
Arapaho Prairie has a long history of summer cattle grazing; in 1976 cattle were removed. In September 1977, 15 (4 m²) permanent plots were randomly established. One, l m² quadrat was selected in each for clipping (to ground level) at the beginning of September over four years (1977-80).
End of growing season biomass (separated by species, dry weight) and litter were measured.
During the 4 years values of annual biomass showed no significant overall increase or decreases; the 1977-1980 average annual end of growing season (September) biomass was 109 g/m².
However, there were significant increases in biomass of the deep-rooted, palatable warm-season (C4) grasses: sand bluestem Andropogon hallii (1.6 to 10.1 g/m²); little bluestem A.scoparius (5.1 to 20.2 g/m²);and switchgrass Panicum virgatum (3.4 to 10.3 g/m²).
The biomass of the shallowly rooted C4 grama (Bouteloua) grasses was correlated with growing season precipitation. Significant decreases in end of season biomass of cool-season (C3) grasses were highly correlated with yearly decreases in May precipitation.
Litter increased from 40 to 128 g/m² from 1977 to 1980. By the forth year, a steady state of litter production and decomposition appeared to have been approached.
The results indicate that productivity (biomass) of large palatable C4 grasses in the Sandhills can increase 2-4 fold in 3 years and 3-6 fold in 4 years, following removal of intense summer cattle grazing.
Note: If using or referring to this published study, please read and quote the original paper, this can be viewed at: https://www.uair.arizona.edu/holdings/journal/issue?r=http://jrm.library.arizona.edu/Volume37/Number1/