This study has been concerned with the patterns of vegetative changes which occur during the first five years following logging and burning on Douglas-fir clear cuts. Knowledge of the successional sequence in the coastal forests of western Oregon is of primary importance to those concerned with the management of this...
A study was initiated in 1961 to characterize seral plant
communities in a part of the Cedar Creek drainage in the Tillamook
Burn. Stratification of vegetation into ecological units was a necessary
first step in conifer-animal damage studies supported by the
Oregon State Game Commission.
Reconnaissance information was recorded in...
A study was undertaken in the Marys Peak watershed with the
following objectives. First, a classification of the major plant communities
was carried out. Second, some of the ecological features
of Acer circinatum that account for its distribution within these
communities were determined. The following plant communities
are described:
Corylus...
Forest associations, secondary succession, and relationships
of plant communities to Roosevelt elk were investigated. Stratification
of vegetation into ecological units and an understanding of secondary
succession by habitat-type were a necessary first step in investigations
into browsing of conifers by elk. The study was jointly conducted
by the Oregon State...
This investigation was undertaken to characterize and evaluate
the forage production and utilization of the successional vegetation
of the mixed conifer forest.
Field studies were carried out during the summers of 1962
through 1964 at the Eastern Oregon Experiment Station Hall Ranch
which is located 12 miles southeast of Union,...
Twelve sites of uniform topography and soils were selected in
the Pinus ponderosa/Purshia tridentata/Festuca idahoensis Association.
These sites were located in the rain shadow on the east flank
of the Oregon Cascades. A fire history in the form of fire scars on
ponderosa pine was available for nine of these...
Seven sites of uniform topography and soil were selected within
a self perpetuating ponderosa pine forest found on the eastern
flank of the central Oregon Cascades. These plots were located along
a vegetational gradient caused mainly by an orographic rain shadow.
Data gathered included density, frequency, and cover for all...
Respiratory rates were measured, in situ, for the litter, the
soil, and the litter-soil subsystems of a Pseudotsuga menziesii forest
as a function of type of understory vegetation. The major objectives
were to demonstrate the utility of the litter layer as a distinct subsystem
of this forest ecosystem, to demonstrate...
Numerous isolates of Armillaria mellea were obtained within
a 250 by 450 foot Study Area in a ponderosa pine plantation in central
Oregon. These isolates were recovered from roots of armillaria-killed
young-growth pine, from large stumps of the former pine
overstory, including roots away from the stump proper, and from...
A three-year investigation was conducted during 1980-1982 to
evaluate the potential of using herded sheep as a silvicultural tool
to suppress brush in Douglas-fir (Pseudotsuga menziesii) plantations
of Oregon's Coast Range. Sheep browsing of Douglas-fir was highest
in May soon after bud break. Averaged over the 2 years of grazing,...
Although there has been extensive research on the geomorphic and ecologic role of
large woody debris (LWD) in streams, the dynamics of LWD in streams are poorly
known due to various measurement difficulties during floods. In this thesis I present the
results of two flume experiments on the dynamics of...
Despite the critical ecological roles of structural features in forests, ecologically
relevant quantitative measures of structure that allow comparisons among forest stands
are still limited. A new index, the structural complexity index (SCI), was developed to
characterize and compare the structural complexity of different forests. Point patterns
of stem-mapped trees...
The juvenile development of Douglas-fir, red alder and snowbrush
associations was investigated in western Oregon. The relationship
between Douglas-fir and red alder was studied and compared
in the Coast, Willamette Valley and Cascade regions. Snowbrush-
Douglas-fir stands were sampled in the western Cascades. Alder-
Douglas-fir relationships were studied on clearcuts...
Nitrogen, phosphorus and sulfur concentrations were measured in the soil, foliage and litter of Douglas-fir growing in pure Douglas-fir and mixed conifer stands. On four sites of contrasting fertility and climatic conditions, plots had been modified by the introduction of alder, thinning, or by a single application of nitrogen fertilizer...
The initial distribution of organic arsenical silvicides was
measured in the trees, litter and soil of four forest types in the
Pacific Northwest following a standard, precommercial chemical
thinnning. Factors which influenced the persistence, movement or
fate of these compounds were noted and used to evaluate differences
in the generalized...
A greenhouse bioassay was used to investigate effects of natural and manmade disturbances on native ectomycorrhizal populations of Douglas-fir and western hemlock on a steep southeast slope in the
west central Cascade Mountains. Total and mycorrhizal root tips were counted on seedlings grown in soils collected from (a) two 100+...