Nature of the Plant Community. I. Uniform Garden and Light Period Studies of Five Grass Taxa in Nebraska

Abstract

Clones representing 5 grass taxa were grown in a uniform garden at Lincoln, Nebraska. In each of the taxa[long dash]Bouteloua gracilis, B. curtipendula, Panicum virgatum, Andropogon scoparius, and the A. gerardi-A. hallii complex[long dash]the earliest flowering clones were from the western part of the state. Clones from progressively more eastern localities exhibited a tendency to flower at progressively later dates. The community sites in the southeastern part of the state contained the later flowering clones of all taxa represented. Clones of B. gracilis, B. curtipendula, and A. scoparius from 5 community sites were grown under 14 hour, 16 hour, and regular increasing light periods from Feb. to June. Under a particular light period, the western material was earlier flowering, and the eastern material was later flowering. It was concluded that the occurrence of the same series of taxa together at different sites does not afford a safe criterion for judging the habitats to be the same. In any particular habitat of the grassland type of community, there has been a selection of ecotypic variants within a number of different taxa for conditions which exist at that site.