The study was conducted over approximately 191,000 acres in central Klamath County, Oregon. The research had three objectives: first, to describe and classify the seral and near-climax vegetation by using polyclimax principles; secondly, to determine the southern extension of five plant associations and one plant associes as previously described by...
In 1957 three Douglas-fir stands (15-, 25-, and 40-year-old age classes) were selected on a tree farm in the Cascade foothills of
northwestern Oregon to study factors affecting site productivity. Soil-moisture, soil-temperature and seasonal radial- growth pattern measurements were made with a Colman moisture meter and a dial gauge dendrometer...
Chemical and microbial analyses were made at four seasonal intervals on soil horizons under red alder, conifers, and mixed
alder-conifers at the Cascade Head Experimental Forest, established in 1937 by the U. S. Forest Service near Otis, Oregon.
Microbial analyses showed that although plate counts of molds and bacteria fluctuated...
The understory vegetation was sampled in eight plant communities
of a Douglas-fir ecosystem to determine the organic matter
production and mineral composition.
Four sample sites were selected in each plant community and
the understory vegetation sampled using the method of quadrats of
successively increasing size. All herbaceous plants were separated...
Humus is one of the important factors controlling the soil
formation process. The nutrients released from it during the decomposition
process also affect the growth and reproduction of the
forest. The type of humus formed is influenced by the nature of the
forest litter and the environment in which it...
Goals in 1972 included characterization of the soils of the
Oregon IBP reference stands, development of information on the soils
throughout the H. J. Andrews Experimental Forest, and evaluation
of nutrient provision to the major kinds of soils. Field reconnaissance,
soil morphology studies, and sampling were carried out.
Lab analyses...
Field and laboratory studies are being conducted to describe the hydrologic properties of soil and to determine the timing pathway of precipitation and snowmelt water as it moved through forested soil on a steep slope. Hydrologic properties include hydraulic conductivity, porosity, pore-size distribution, moisture characteristics, stone content, and soil depth....
The conceptual framework of an erosion model has been designed to link processes of mass wasting, surface erosion, and channel storage and transport. A program to stimulate mass wasting will be based on a variation of the factor of safety approach which balances forces tending to drive mass movement against...
During Biome 1, our primary objective was identification of the dominant fungi involved in litter decomposition. Two survey methods
were used: (1) a survey of macrofungi occurring on Watershed 2 based on fruiting bodies collected and cultures; and (2) a survey of microfungi on decomposing foliage based on cultures isolated...
Findley Lake watershed is located in the Snoqualmie National Forest and has a surface area of 259 ha (1 Mi²). The lake is at an elevation of 1128 m (3701 ft) but the ridges attain elevations of 1450 m (4750 ft).
The Cougar Mountain Formation, consisting of lava flows, conglomerate,...
This is the annual report from the investigators responsible for soil
characterization at the Findley Lake watershed. Soil characterization
is complete for two soils and is in progress on six others. Site
preparation for years 3 and 4 is complete except for lysimeter
installation.
Early in the planning of the Coniferous Biome program It was recognized that experimental watersheds 2 and 3 in the H. J. Andrews Experimental Forest might provide ideal study sites for certain phases of the Biome
program. A study was funded during year 1 (1970) to provide necessary background ecological...
Early in the planning of the Coniferous Biome research program, it was recognized that Experimental Watersheds 6, 7, and 8 in the
H. J. Andrews Experimental Forest might provide ideal study sites for certain phases of the Biome program. A study was funded during year 1 (1970) to provide necessary...
Data on soil temperature at two locations and five depths, tensiometer readings, and soil moisture release curves for the soils of Findley Lake are presented in this report.
Air temperatures at i m and soil temperatures at 2C cm are reported for
twenty-one forest stands in the central Western Cascader of Oregon. Records
began in 1970 for some stands, in 1971 or 1972 for most. Temperature Growth
Index for a stand, based on temperature effects on Douglas-fir seedling...
Field reconnaissance, soil sampling, and laboratory analyses were
conducted to characterize the soils of the 50 by 50 meter forest community
reference stand plots in and near the H. J. Andrews Experimental
Forest. Soil descriptions, chemical and physical properties, soil classification,
and nutrient capital information for mineral soils are summarized....
Measurement of plant moisture stress of 1-2 m understory conifers
was made in "reference stands" on the H. J. Andrews Experimental
Forest in 1970-1972. Maximum stress each year (measured between midnight
and dawn) is closely correlated with the position of each community
along one axis of an ordination of the...
The following report Introduces a documentation scheme for flow
oriented ecosystem models and shows its application to a carbon-water
model developed within the coniferous biome. This documentation scheme
has remained operative through revision of this model and expansion of
It to include nutrient flows. This model and subsequent versions are...
The purpose of this study was to examine certain hydrologic
properties of the soil and subsoil on a steep forested slope and relate
these -rceTties to the movement of water via subsurface routes.
The hydrologic properties examined were bulk density, soil texture,
total porosity, pore size distribution, saturated hydraulic conductivity,...
The work upon which this publication is based was supported by funds provided by the United States Department of the Interior, Office of Water Research and Technology, as authorized under the Water Resources Research Act of 1964 and by the United States Department of Agriculture, Forest Service, Pacific Northwest Forest...
Published January 1976. Reprinted March 1978. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Monitoring soil density on three sites during repeated trips with a high-speed skidder showed that: During the first 20 trips, soil density primarily increased between depths of 2 to 4 inches; Density increased most during the first few trips; Density continued to increase slowly in amount and depth with the...
Surface erosion can be initiated by forest practices such as
timber harvest, road construction, and site preparation. A variety
of management and control measures can help reduce
this erosion. Surface erosion is generated by soil and operational
conditions that are conducive to or cause disturbance
and compaction. By using good...
Published August 1980. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The variability of selected physical, chemical, and morphological
soil properties in two landtype mapping units on'the Rogue River National
Forest in southwestern Oregon was studied.
The objectives of the study were (i) to quantify soil variability
in several soil resource inventory mapping units, (ii) to explore methods
of describing soil...
This study evaluated the effects of a crawler tractor, a rubber-tired skidder, and a torsion suspension vehicle on several soil and hydrologic properties in the western Sierra Nevada Mountains of California. Four sites, with soil textural classes ranging from a loam to a loamy sand and elevations between 680 and...
The strength of both undisturbed and compacted soils from 10 sites
in the slide-prone Tongass National Forest in SE Alaska were studied.
Index property tests were also conducted on disturbed samples. The
index tests included natural water content, Atterberg Limits, specific
gravity of solids, grain size distribution, and moisture-density relationship....
Published December 1981. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
This study was undertaken to determine both the amount and the
spatial variability of sand, silt, clay, and six fractions of coarse
fragments in soils representing harsh sites for reforestation. Particle size data were collected because of their direct relationship to
water holding capacity and the plantability and survivability of...
Tillage of forest soils compacted by ground-based logging systems is a practice that is becoming widely accepted in the Pacific Northwest. However, past research has failed to adequately define the conditions and specifications that particular tillage operations should meet in order to produce the maximum growth response from planted seedlings....
Measurements for water retention calculations and physical
characterization were made on skeletal and non-skeletal soils in
southwest Oregon. A new bulk density sampler was designed for the
physical characterization of the steep, skeletal soils commonly
encountered in this area. The new sampler and the techniques
required for the measurement and...