A COMPARISON OF THE WOODY VEGETATION IN ADJACENT UPLAND AND RIPARIAN AREAS INHABITED BY BEAVER (CASTOR CANADENSIS).

Woody vegetation in 30 quadrats, 15 each in a riparian and upland area of an urban forest located in Marshall, TX (32°33′N; 94°22′W), was assessed for relative frequency, relative density, relative dominance, and importance. Additionally, the riparian area and adjacent upland area were assessed for the potential impact of beaver in the riparian area. The most important tree species in the canopy were white oak {Quercus alba), southern red oak (Q. falcata), loblolly pine (Pinus taeda), slippery elm (Ulmus rubra), and sweet gum {Liquidambar styraciflua). Beech (Fagus grandifolia) and red maple (Acer rubrum) were found in the understory in greater frequencies than in the canopy. Composite species richness was 16.9 ± 1.8 in the canopy. The species richness of the riparian area was moderately higher (12.8 ± 1.5) than the upland area (11.8 ± 1.5), but not significantly different (z = 0.577; P = 0.282). The Shannon-Wiener index of diversity was greater for the upland area (2.86 bits) than the riparian area (2.57 bits). The Morisita coefficient of similarity between the two areas was 0.84 in the canopy and 0.97 in the understory. [ABSTRACT FROM AUTHOR]