Canopy gap formation is a major factor contributing to maintenance of overstory species diversity and stand structure in forests and may be integral to development of understory shrub and herb layers as well. Acknowledgement of gap formation as a fundamental feature of natural forests has led to consideration of gaps...
Previous observations of light levels and phytoplankton abundances along the Oregon coast demonstrated that phytoplankton attenuated light sufficiently to potentially limit the growth of intertidal macrophytes and therefore structure local intertidal communities. Inspired by this observation, in spring 2004, I initiated a study to quantify the direct and indirect benthic...
Four studies were conducted on late-summer diet quality and quantity of cattle (Bos taurus), mule deer (Odocoileus hemionus hemionus), and elk (Cervus elaphus) in response to prior grazing by cattle and elk on mixed-conifer rangelands and on related research techniques. In our first study we assessed a photographic technique to...
Although the Pacific Northwest has the least proportion of non-native plant species in relation to other regions of North America, exotic species continue to spread into mountainous areas, including the Cascade Range. In a forested landscape, road networks can act as corridors for exotic plant dispersal and establishment, helping species...
Juniper is a native species to Oregon and confers ecological benefits to wildlife when it is at savannah and transitional densities. Its range and extent have fluctuated with climatic change, but the current range expansion is unprecedented in its extent. The range expansion has been associated with the degradation of...
Thirteen different habitat parameters were measured either quantitatively or
qualitatively around seven different Salix (willow) species on a defined reach of stream
on the southwestern slope of Steens Mountain in southeastern Oregon in order to both
broaden the current information base of riparian ecology and inform future willow
plantings aimed...
The purpose of this study of the Lyons flora is to determine the age and paleoecology of the flora through the examination and identification of the fossil plant species of the flora. The plant fossils comprising the Lyons flora were collected from a locality in the upper Thomas Creek area,...
The specificity of quantitative host resistance to plant disease has long been a controversial issue. We examined interactions between wheat (Triticum aestivum) and Mycosphaerella graminicola, causal agent of Septoria tritici blotch, to determine whether specific interactions occur between host and pathogen genotypes that could be involved in eroding quantitatively expressed...