The response to various levels of stand density by natural Douglas-fir regeneration, shrub and sprouting hardwood species was studied in the mixed-evergreen-forests of southwest Oregon. Partial-cut old growth (harvested 22-31 years prior) and thinned evenaged (harvested 9-17 years prior) stand types were used as surrogates for intentionally managed uneven-aged stand...
Although buffer strips have long been used as a
protection tool when logging near streams, long-term
studies investigating buffer strip dynamics are rare.
Steinblums et al. (1984) inventoried 40 buffer strips 1 to
15 years old in the western Oregon Cascades beginning in
the summer of 1975. Numerous site and...
The differential effect of solar radiation on seedling establishment under a forest stand was studied to develop a basis for controlling species composition in the regenerating stand. The study was carried out on the Oregon Coast where current silvicultural practice is to clearcut mature stands and establish Sitka spruce (Picea...
Studies were conducted within a 12-mile radius of Camp Sherman, Oregon, in the Deschutes National Forest during the spring and summer of 1965 and the spring of 1966, with one follow-up visit in the summer of 1967. The feeding and foraging activities of Eutamias amoenus and Citellus lateralis were observed,...
This study was started in 1947 to investigate the value of various types and quantities of seed source in the establishment of reproduction on cutover land, and to determine the apparent effects of various man-made and natural factors upon the rate of restocking. The man-made and natural factors to be...
Future scenarios of global climate change rely on large-scale climate envelope models that do not account for local climatic conditions to which organisms most closely respond. Shifts in species distributions and phenology driven by climate change are well-documented, yet we lack a strong understanding of how climate change will influence...
These studies are part of the Demonstration of Ecosystem Management Options (DEMO) study, a program researching the effects of different levels and patterns of green-tree retention on ecological, economic, and social phenomena. We restricted our studies to the 15% basal area, evenly dispersed retention treatment. Our objectives were, first, to...
From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black rockfish extruded larvae earlier in the season, followed by progressively younger fish. Each year, beginning in May, I collected young-of-the-year (YOY)...
Natural Douglas-fir stand development is the result of
many types of disturbance, both natural and management
induced. The magnitude and timing of these disturbances
have profound effects on the structure and composition of
both the overstory and understory plant communities. Vine
maple responds to disturbance by basal sprouting, layering,
producing...
This annotated bibliography was compiled to provide a comprehensive list of sources on the ecological factors that affect forest regeneration. Abstracts from 494 publications are indexed by author, species, and subject, and are arranged into 4 major sections. Topics include the effects of biotic factors, abiotic factors, and stand and...
Fire severity is hypothesized as an important driver of bird responses to wildfire. For those species that typically respond negatively to increasing severity, Accessibility of high-severity burned forest may be dependent on the proximity of unburned or low-severity burned forest to meet all of the needs of breeding bird species...
a. Overview -- b. Vine maple : Acer circinatum Pursh -- c. Red alder : Alnus rubra Bong. -- d. Tanoak : Lithocarpus densiflorus (Hook & Arn.) Rehd. -- e. Salmonberry : Rubus spectabilis Pursh -- f. Glossary -- g. Associated literature.
Published November 1943. 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 Mount St. Helens eruption of May 18, 1980, offered an
excellent setting for evaluating early response of ecosystems to
disturbance. Prior to the eruption, the area was densely forested
with fir, hemlock, and Douglas-fir, and various understory species.
During the course of the eruption, hillslopes within a 180 degree...
National Forest management in the Pacific Northwest is shifting
from a focus on commodity production to ecosystem management, in which
the health of the entire forest ecosystem is considered, rather than that
of a few key species. Ecosystem management includes retention of some
live trees following timber harvest (green-tree retention)...
Nest sites of reticulate sculpin (Cottus perplexus) were located in two stream reaches, one from a basalt basin and one from a sandstone basin. Stream reaches were similar in gradient, basin area, elevation, climate, and riparian vegetation but differed in biologic community structure and substrate characteristics. An electivity index was...
Identifying habitat and spatial requirements of wildlife species across multiple spatial scales is a challenging, yet crucial component of wildlife management. Habitat use of bats is particularly difficult to study, and managing habitat to conserve bats is especially challenging because bats are highly vagile organisms that exploit several different types...
Habitat use and reproductive success by Merriam's wild turkey
(Meleagris gallopavo merriami) were studied in Wasco County, Oregon,
during 1981-82. This low density turkey population selectively used
forested cover types characterized by a variety of structural
features, species, and age classes. They avoided monotypic forested
cover types, used non-forested cover...
A severe wildfire burned 454 hectares of a second-growth Douglas-fir forest
in 1977 on a north-facing slope in Pattee Canyon, near Missoula, Montana. The
slope was aerially seeded with a grass mixture, from which Dactylis glomerata
established best. Community structure, conifer regeneration, and the impact of the
seeded grass on...
A field study was established to explore stand structure and development patterns of
mature, mixed-species forests in the Interior Cedar-Hemlock (ICH) zone: moist cold
subzone of northwestern British Columbia. The species of interest in the study area
were: western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja
plicata Donn), lodgepole...
Black rockfish (Sebastes melanops) is an important marine recreational species throughout the Pacific Northwest. Recent catch data indicate a trend of age-truncation in the black rockfish population off the Oregon coast, with older females rapidly disappearing from the population. In populations with broad age distributions, older fish may contribute disproportionately...
Great blue heron (Ardea herodias) eggs and prey items were collected from six colonies on the Columbia and Willamette rivers and Puget Sound during 1994-95. Contaminant concentrations, reproductive success, and biomagnification factors (BMFs) were determined and effects of residue levels were measured by H4IIE rat hepatoma and ethoxyresorufin-O-dealkylase (EROD) bioassays....
The objectives of this study were to determine the species composition and density of natural conifer regeneration following selective logging in southeast Alaska.
Therefore, we quantified the density and size of new cohort spruce and hemlock and current seedling bank in 17 selectively logged stands. All stands were in mixed...
Northern Spotted Owls (Strix occidentalis caurina) are a long-lived forest owl and range-wide declines in their numbers have resulted in the species being listed as threatened under the endangered species act. While many studies have been focused on population trends and reproductive performance of Spotted Owls from different age-classes, none...
I monitored demography, movement, and reproductive behavior of gray-tailed voles, Microtus canicaudus, in experimental habitat patches with and without corridors. I tested the hypotheses that reproductive rate, juvenile recruitment, and population size and growth rate would be affected negatively by immigrants that were introduced to resident groups (+ male and...
From 3 April – 21 September 2007, we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek,...
From 2 April – 14 September 2006, we monitored the distribution, abundance and productivity of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River estuary, the Dunes overlook, North Tahkenitch Creek,...
From 1 April – 24 September 2008, we monitored the distribution, abundance and productivity
of the federally Threatened Western Snowy Plover (Charadrius alexandrinus nivosus) along the Oregon
coast. From north to south, we surveyed and monitored plover activity at Sutton Beach, Siltcoos River
estuary, the Dunes Overlook, North Tahkenitch Creek,...
Greater sage-grouse (Centrocercus urophasianus) populations declined range wide during the past 50 years. Grouse populations were 2-3 times larger than the current population as recently as the early 1970's. In addition to habitat loss and fragmentation, declines were attributed habitat degradation that caused reduced productivity. Because chick survival remains the...
The forests of the Oregon Coast Range have been both the principal
natural resource, and for many years, the primary economic base of the region. In the past thirty years, changing social and economic factors have created new visions for these forests, leading to conflict over the appropriate management of...
Much of the native riparian vegetation of the Willamette Valley, Oregon, has been replaced with agricultural crops or invasive non-native plant species. Detailed information about current Willamette Valley riparian vegetation is generally lacking. Plant specie composition data are useful in a variety of applications, including condition assessment, environmental monitoring and...
Bumble bees provide vital pollination services in both native and agricultural landscapes. However, in recent years, bumble bee populations have experienced global population declines. The primary causes of these declines have been attributed to the environmental impacts of pathogens, pesticide use and habitat fragmentation. While research has examined the impacts...
Since the early 1990s, declines in northern spotted owl (Strix occidentalis caurina) populations have been documented through extensive field surveys and range-wide demographic analyses. Although loss of late-successional forest has been credited as the primary cause for spotted owl population declines, environmental variation has also been shown to influence vital...
In the preparation of this thesis, the writer does not claim to have discovered any great truths or their underlying causes. As the title indicates, the work is a summary of some of the more important investigational activities on the McDonald Forest. This line of endeavor was chosen because it...
Environmental stress can negatively affect the ability of organisms to reproduce. Energetic trade-offs exist in all organisms, and under stress, energy may be allocated away from reproduction and towards physiological defense and repair mechanisms. The rocky intertidal environment is ideal for investigating the influence of environmental stress, as organisms are...