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Filtering by: Committee Member Hansen, Everett Decade 1980-1989

Insects associated with black stain root disease of Douglas-fir in western Oregon

Creator:

Witcosky, Jeffrey John

Abstract:

The root systems of Douglas-fir trees infected with Verticicladiella wagenerii and assigned by crown color and terminal growth characteristics to several stages of decline were excavated at three widely separated sites in the Coast Range of Oregon. Data were gathered on insect species present, extent of colonization of the root...

Resource Type:

Masters Thesis

Full Text:

my minor professor Dr. Everett Hansen for his unwavering confidence and financial support of my
The spatial distribution of wood-nesting ants in the central Coast Range of Oregon

Creator:

Nielsen, Gary R. (Gary Richard), 1956-

Resource Type:

Dissertation

Full Text:

thank Dr. Everett Hansen and Dr. Donald Zobel for loaning field and laboratory equipment to me. I am
Logs as sites of tree regeneration in Picea sitchensis-Tsuga heterophylla forests of coastal Washington and Oregon

Creator:

Harmon, Mark E.

Abstract:

Logs are seedbeds for trees in many Picea sitchensis-Tsuga heterophylla forests of Washington and Oregon. Factors affecting this close association, including seed retention and seedling establishment on logs and successional changes in log characteristics, are explored In this study. Field and laboratory experiments indicated that competition with vegetation on the...

Resource Type:

Dissertation