Phenological Properties of Wind‐ and Insect‐Pollinated Prairie Plants
1981
Rabinowitz, Deborah | Rapp, Jody K. | Sork, Victoria L. | Rathcke, Beverly J. | Reese, Gary A. | Weaver, Jan C.
The number of flowering stems for 82 species on a transect 2 x 400 m was counted twice weekly during 1978 at Tucker Prairie, Callaway County, Missouri, USA, a tall—grass prairie remnant. Phenological curves (number of flowering stems vs. day of the year) are narrower (smaller standard deviations) for wind—pollinated species than for insect—pollinated species. Symmetry (g1) does not differ significantly for wind— and insect—pollinated species. The curves are largely either symmetric or begin abruptly and end gradually (right—skewed). Overlap, measured as the fraction of the area under the curves occupied by two or more species, does not differ significantly for wind— and insect—pollinated species, among 20 groups of five randomly drawn species. Dates of peak flowering are distributed randomly over the season (May to November 1978) and their distributions do not differ for wind— and insect—pollinated species. Dates of peak flowering are also randomly distributed for grasses, legumes, and composites considered separately. Thus, although species with different pollination modes show different shapes for phenological curves, the species aggregated into the community do not have ensemble patterns of temporal dispersion or overlap and cannot be distinguished from a random collection.
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