Pseudotsuga menziesii dominates the forests of the Pacific Northwest.
But though it is dominat, Tsuaa heteroohylla or Abies amabilis
is usually climax. Many researchers have studied Pseudotsuga on the
widespread mesic sites where it is seral, but few have examined the
relatively rare ecosystems in which Pseudotsuga or its associate...
Large organic debris has important biological and physical
roles within the stream ecosystem. In order to determine the source
area of large organic debris in streams, thirty-nine streams in the
Cascade and Coast Ranges of Oregon and Washington were sampled. The
distance from point-of-origin to channel was measured for thirty...
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...
The structure of a mature Douglas-fir (Pseudotsuga menziesii)
forest in a watershed in the western Cascades of Oregon was examined.
Two age classes were detected in the stand, the oldest originating
about 1855 after an extensive fire and the younger following a second
fire about 1895 Although the trees in...
Information concerning the factors controlling seedling establishment on tephra deposits (airfall volcanic ejecta) is limited. The establishment and growth of six coniferous species, Abies amabills (Dougl.) Forbes (Pacific silver fir), A. procera Rehd. (noble fir), Pinus monticola Dougl. (western white pine), P. Contorta Dougl. (lodgepole pine), Pseudotsuga menziesii (Mirb.) Franco...
The rate and manner of bioniass loss from decomposing Douglas-fir and western hemlock boles in mid-elevation forests of the central Cascade Range were measured. Bole bark and wood were considered separately. Loss of bole wood due to respiration was measured by change in bole wood density. Loss of bole wood...
This study dealt with research problems at the landscape level. The objectives of this thesis were to develop tools to study and characterize landscapes and to interface with a geographic information system (GIS), to evaluate landscape indices, and to examine development of forest cutting patterns under different cutting methods and...
