Abundance and Neighborhood Structure for Sparse and Common Grasses in a Missouri Prairie

Biomass abundance and distance from a random point to the nearest flowering culm were measured during two seasons for eight species of native perennial grasses on a continuum from locally rare to common in a Missouri tall prairie. Mean abundance from the most common to the most rare ranges over three orders of magnitude (nine octaves) from 73 to .25 g/m 2 . The means of the distance to a culm range over two orders of magnitude (four octaves) from 0.3 m to 5.0 m. The logarithm of distance to a culm is linearly correlated with the logarithm of abundance. Distance to an inflorescence is greater for sparse species than for common species.