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Date Permissions Signed


Date of Award

Winter 1990

Document Type

Masters Thesis

Degree Name

Master of Science (MS)


Environmental Sciences

First Advisor

Matthews, Robin A., 1952-

Second Advisor

Robbins, Lynn A.

Third Advisor

Taylor, Ronald J., 1932-


This study examines the cause, distribution and impact of a forest pathogen within the 71 forested hectares of the Sehome Hill Arboretum in urban Bellingham, Washington. The causal agent was determined by the identification of cultures from decaying wood in douglas fir (Pseudotsuga menziesii (Mirbel) Franco) to be the root rotting basidiomycete Phellinus weirii (Muir.) Gilb. A ground survey of aboveground symptoms was used to detect 31 infection centers covering 6.64 hectares (9.2% of the Arboretum) of symptomatic trees. Infra-red aerial photography was used to determine canopy cover for deciduous and evergreen species. A forest canopy survey was conducted to determine canopy dominance in each of 22 forested regions of the Arboretum. Basal area at breast height was used to establish dominance. Tree density and size-class distributions were used to predict future dominance in the presence of continuing Phellinus root rot infection. Seven management approaches were discussed.




Forest pathogens


Western Washington University

OCLC Number


Subjects – Names (LCNAF)

Sehome Hill Arboretum (Bellingham, Wash.)

Subject – LCSH

Douglas fir--Washington (State)--Bellingham; Phellinus--Washington (State)--Bellingham; Root rots

Geographic Coverage

Bellingham (Wash.)




masters theses




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