The Vascular Flora of McKinney Roughs Bastrop County, Texas

Abstract

The Lower Colorado River Authority opened McKinney Roughs in Bastrop County, Texas, to the hikers and equestrians in 1996. Past uses of the 648-hectare tract near the western margin of the Oak Woodlands include farming, ranching, and surface mining. The vascular flora was surveyed during the growing seasons of 1999 and 2000 and a series of line-intercept transects was used to determine the composition of the leastdisturbed woodland and forest stands. Qualitative data collected along these transects were used to represent the stands in ordination space and to refine the classification of the woody plant communities on-site. The flora consisted of 372 species in 284 genera and 93 families. Non-native species constituted 8.9 percent of the flora. Cluster analysis indicated the presence of one woodland and six forest associations on the property. The upland associations were a Juniperus virginiana-Quercus stellata-Quercus marilandica woodland, Q. stellata-J. virginiana-Carya texana forest and /. virginiana-Q. stellataUlmus crassifolia forest. Ravines along slopes leading to the Colorado River were characterized by Q. stellata-J. virginiana-Fraxinus texensis and Pinus taeda-Q. stellataQ. marilandica forests, while the terraces of the Colorado River floodplain were occupied by Ulmus americana-Celtis laevigata-Salix nigra and U. crassifolia-C. laevigataQuercus sinuata forests.