Date of Award


Document Type


Degree Name

Master of Arts (MA)



First Advisor

Dr. Thomas Bragg


Changes in species composition of a Bluestem prairie were evaluated under isolated, 10-22 year old Juniperus virginiana (Eastern Red Cedar) in eastern Nebraska. Percent canopy cover was measured in full-canopy, canopy-edge, and open-canopy plots which were located along transects oriented to the cardinal compass directions. A total of 53 species were recorded. Andropogon scoparius and A. gerardii dominated open-canopy and canopy-edge plots; Poa pratensis and A. scoparius dominated full-canopy plots. Canopy cover of most prairie species decreased under full canopy but Poa pratensis and Carex spp. increased. There was a positive correlation between tree size and both the decrease of prairie species and the increase of Poa pratensis under a full-canopy. Similarly, aspect was significantly correlated to changes in species composition under a full-canopy. For those species with significant differences between cardinal directions, canopy cover was lowest on the north and east transects. The results of this study show that invasion of woody plants into native prairie rapidly affects the composition of native grassland species.


A Thesis Presented to the Department of Biology and the Faculty of the Graduate College University of Nebraska In Partial Fulfillment of the Requirements for the Degree Master of Arts University of Nebraska at Omaha. Copyright 1983 Janet L. Gehring.