Browsing Theses and Dissertations (Botany and Plant Pathology) by Author "Zobel, Don"

Now showing items 1-4 of 4

The effects of nitrogen manipulations and hydrology on the establishment and competitive abilities of wetland prairie plant species (western Oregon)

Davis, Kimberly J. (2000-08-15)

Many studies suggest that weedy plant species are most successful when soil nitrogen in abundant. Consequently, I used soil nitrogen manipulations to determine if altering nitrogen would affect the establishment of bot ...
Effects of single and multiple stressors on communities of wheat and wild oats

Pfleeger, Thomas G. (1998-05-01)

Most plant toxicology tests developed in support of environmental laws use a single stress applied to an individual plant. While tests using individual species or stresses require fewer resources and are easier to interp ...
Morphological and cytological variation in Trillium albidum Freeman (Liliaceae)

Bledsoe, Karen E. (1993-03-15)

This work was performed on Trillium albidum Freeman (Liliaceae), to clarify the pattern of morphological variation between the small-flowered populations at the northern limit of its range ( T. parviflorum Soukup) and ...
Port-Orford-cedar and Phytophthora lateralis : grafting and heritability of resistance in the host, and variation in the pathogen

McWilliams, Michael G. (2000-06-06)

Port-Orford-cedar (Chamaecyparis lawsoniana) is a forest tree native to a small area of Oregon and California. A root disease caused by Phytophthora lateralis causes widespread mortality of Port-Orford-cedar. This dis ...