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• 1. [Article] Key to the deciduous woody plants of Northwestern Oregon in winter

  Citation × Citation Citation Abstract Copy Title: Key to the deciduous woody plants of Northwestern Oregon in winter Author: Packard, Patricia Lois Title: Key to the deciduous woody plants of Northwestern Oregon in winter Author: Packard, Patricia Lois Close

• 2. [Article] Lead exposures in radiator shops in a nine-county area of northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Lead exposures in radiator shops in a nine-county area of northwestern Oregon Author: Burnham, John William Title: Lead exposures in radiator shops in a nine-county area of northwestern Oregon Author: Burnham, John William Close

• 3. [Article] Distribution and characteristics of loess-like soil parent material in northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Distribution and characteristics of loess-like soil parent material in northwestern Oregon Author: Theisen, A. A. (Arthur A.) Title: Distribution and characteristics of loess-like soil parent material in northwestern Oregon Author: Theisen, A. A. (Arthur A.) Close

• 4. [Article] A forest land use policy for northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: A forest land use policy for northwestern Oregon Author: Allison, Grant W. Title: A forest land use policy for northwestern Oregon Author: Allison, Grant W. Close

• 5. [Article] Effect of release by logging on diameter growth of residual hemlock in northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Effect of release by logging on diameter growth of residual hemlock in northwestern Oregon Author: Kimmey, Ray I. Title: Effect of release by logging on diameter growth of residual hemlock in northwestern Oregon Author: Kimmey, Ray I. Close

• 6. [Article] Distribution and taxonomy of the small pocket gophers of northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Distribution and taxonomy of the small pocket gophers of northwestern Oregon Author: Walker, Kenneth Merriam Title: Distribution and taxonomy of the small pocket gophers of northwestern Oregon Author: Walker, Kenneth Merriam Close

• 7. [Article] Age determination and age-specific reproduction in raccoons in northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Age determination and age-specific reproduction in raccoons in northwestern Oregon Author: Fiero, Brad C. Title: Age determination and age-specific reproduction in raccoons in northwestern Oregon Author: Fiero, Brad C. Close

• 8. [Article] Estimating streamflow characteristics for micro-hydro sites in northwestern Oregon

  A methodology for estimating streamf low characteristics on Ungaged streams was developed for northwestern Oregon. Basin area and basin area multiplied by the square root of relief were found to be effective ...

  Citation × Citation Citation Abstract Copy Title: Estimating streamflow characteristics for micro-hydro sites in northwestern Oregon Author: Lieuwen, Andrew L. A methodology for estimating streamf low characteristics on Ungaged streams was developed for northwestern Oregon. Basin area and basin area multiplied by the square root of relief were found to be effective independent variables in regression models for estimating the average annual flow, the average daily flood with a two-year recurrence interval, and the seven day average low flow with a twoyear recurrence interval. A method for constructing synthetic flowduration curves from estimates of these three flow characteristics is described. These synthetic flow-duration curves provide important information for assessing hydropower potential for micro-hydro sites in this region. Title: Estimating streamflow characteristics for micro-hydro sites in northwestern Oregon Author: Lieuwen, Andrew L. A methodology for estimating streamf low characteristics on Ungaged streams was developed for northwestern Oregon. Basin area and basin area multiplied by the square root of relief were found to be effective independent variables in regression models for estimating the average annual flow, the average daily flood with a two-year recurrence interval, and the seven day average low flow with a twoyear recurrence interval. A method for constructing synthetic flowduration curves from estimates of these three flow characteristics is described. These synthetic flow-duration curves provide important information for assessing hydropower potential for micro-hydro sites in this region. Close

• 9. [Article] Food and habitat partitioning in two groups of coexisting Accipiter

  Sharp-shinned Hawks (Accipiter striatus), and Cooper's Hawks (A. coo erii) in the conifer forests in northwestern Oregon and A. striatus, A. cooperii, and Goshawks (A. gentilis) in the conifer forests ...

  Citation × Citation Citation Abstract Copy Title: Food and habitat partitioning in two groups of coexisting Accipiter Author: Reynolds, Richard T. Sharp-shinned Hawks (Accipiter striatus), and Cooper's Hawks (A. coo erii) in the conifer forests in northwestern Oregon and A. striatus, A. cooperii, and Goshawks (A. gentilis) in the conifer forests of eastern Oregon were syntopic during the nesting season. In this study density of nests, nest success, and utilization of food and habitat resources by each Accipiter in both northwestern and eastern Oregon were determined for 1969 through. 1974. Abundance of birds and small, diurnal mammals in the forests of eastern Oregon and the abundance of birds in the forests of northwestern Oregon were estimated in faunal surveys of a variety of conifer forest types. In addition, the occurrence of small mammals in eastern Oregon and their relative abundances were qualitatively estimated. The physiography and vegetative structure of Accipiter nest sites were quantified in both study areas, and differences in habitat variables among the sites of each species were examined by multivariate analysis of variance and discriminant analysis. These analyses showed that, while nest sites of each Accipiter in both areas had similar physiographic features, they differed in the structure of the vegetation. These differences were associated with the successional stage of the forest stands selected by each species: A. striatus nested in dense, 40-60-year-old, even-aged stands of conifers, A. cooperii in 50-80-year-old, dense conifer stands with slightly larger, more widely spaced trees, and A. gentilis in dense, conifer stands with large overstory trees and a dense understory of regenerating conifers. The following differences in the prey resources of the two study areas were noted; eastern Oregon had (1) nearly one half the species and density of birds, (2) a size-frequency distribution shifted somewhat toward larger birds, and (3) more species and a greater density of mammals than northwestern Oregon. Mean size of prey (12.8 g) captured by A. striatus in northwestern Oregon was significantly smaller than prey (28.4 g) captured by the same species in eastern Oregon. The diet of A. striatus in both areas was composed almost entirely of birds (<5% mammals). Mean size of prey of A. cooperii in both areas was nearly the same (134.7 g and 136.3 g) and each was significantly larger than mean sizes of prey of A. striatus. However, prey size and taxonomic composition of diets of A. cooperii varied; 74% birds (x = 79.2 g) and 25% mammals (x = 296.4 g) in northwestern Oregon and 47% birds (x = 123.7 g) and 53% mammals (x = 147.5 g) in eastern Oregon. Mean size of prey (306.6 g) of A. gentilis in eastern Oregon was significantly larger than mean size of prey of A. cooperii and consisted of 53% birds (3T = 195.5 g) and 45% mammals (x = 445.2 g). An analysis of the utilization of prey sizes, prey taxa, and foraging height zones demonstrated that partitioning of food in both areas occurred primarily in the prey size dimension. However, A. cooperii and A. gentilis, which broadly overlapped in the size dimension, showed increased partitioning of prey taxa. In eastern Oregon, use of foraging zones by A. cooperii and A. gentilis was nearly identical; both species captured prey primarily from the lower zones (ground-shrub and shrub-canopy). There was, however, little overlap on this dimension between A. striatus and its congeners in either study area as A. striatus almost entirely limited its foraging to the upper canopy. Although it was not determined if food resources were limiting, a review of the feeding ecology of Accipiter in Oregon, in view of some predictions of competition theory, supported the hypothesis that the different body sizes of coexisting members of this genus evolved in response to competition for food resources during the breeding season. Title: Food and habitat partitioning in two groups of coexisting Accipiter Author: Reynolds, Richard T. Sharp-shinned Hawks (Accipiter striatus), and Cooper's Hawks (A. coo erii) in the conifer forests in northwestern Oregon and A. striatus, A. cooperii, and Goshawks (A. gentilis) in the conifer forests of eastern Oregon were syntopic during the nesting season. In this study density of nests, nest success, and utilization of food and habitat resources by each Accipiter in both northwestern and eastern Oregon were determined for 1969 through. 1974. Abundance of birds and small, diurnal mammals in the forests of eastern Oregon and the abundance of birds in the forests of northwestern Oregon were estimated in faunal surveys of a variety of conifer forest types. In addition, the occurrence of small mammals in eastern Oregon and their relative abundances were qualitatively estimated. The physiography and vegetative structure of Accipiter nest sites were quantified in both study areas, and differences in habitat variables among the sites of each species were examined by multivariate analysis of variance and discriminant analysis. These analyses showed that, while nest sites of each Accipiter in both areas had similar physiographic features, they differed in the structure of the vegetation. These differences were associated with the successional stage of the forest stands selected by each species: A. striatus nested in dense, 40-60-year-old, even-aged stands of conifers, A. cooperii in 50-80-year-old, dense conifer stands with slightly larger, more widely spaced trees, and A. gentilis in dense, conifer stands with large overstory trees and a dense understory of regenerating conifers. The following differences in the prey resources of the two study areas were noted; eastern Oregon had (1) nearly one half the species and density of birds, (2) a size-frequency distribution shifted somewhat toward larger birds, and (3) more species and a greater density of mammals than northwestern Oregon. Mean size of prey (12.8 g) captured by A. striatus in northwestern Oregon was significantly smaller than prey (28.4 g) captured by the same species in eastern Oregon. The diet of A. striatus in both areas was composed almost entirely of birds (<5% mammals). Mean size of prey of A. cooperii in both areas was nearly the same (134.7 g and 136.3 g) and each was significantly larger than mean sizes of prey of A. striatus. However, prey size and taxonomic composition of diets of A. cooperii varied; 74% birds (x = 79.2 g) and 25% mammals (x = 296.4 g) in northwestern Oregon and 47% birds (x = 123.7 g) and 53% mammals (x = 147.5 g) in eastern Oregon. Mean size of prey (306.6 g) of A. gentilis in eastern Oregon was significantly larger than mean size of prey of A. cooperii and consisted of 53% birds (3T = 195.5 g) and 45% mammals (x = 445.2 g). An analysis of the utilization of prey sizes, prey taxa, and foraging height zones demonstrated that partitioning of food in both areas occurred primarily in the prey size dimension. However, A. cooperii and A. gentilis, which broadly overlapped in the size dimension, showed increased partitioning of prey taxa. In eastern Oregon, use of foraging zones by A. cooperii and A. gentilis was nearly identical; both species captured prey primarily from the lower zones (ground-shrub and shrub-canopy). There was, however, little overlap on this dimension between A. striatus and its congeners in either study area as A. striatus almost entirely limited its foraging to the upper canopy. Although it was not determined if food resources were limiting, a review of the feeding ecology of Accipiter in Oregon, in view of some predictions of competition theory, supported the hypothesis that the different body sizes of coexisting members of this genus evolved in response to competition for food resources during the breeding season. Close

• 10. [Article] Native freshwater wetland plant associations of northwestern Oregon

  This guide provides keys, descriptions, and stand tables for 122 native freshwater plant associations (14 forest and woodland, 28 shrub, 78 herbaceous, 2 nonvascular) in northwestern Oregon, based on analysis ...

  Citation × Citation Citation Abstract Copy Title: Native freshwater wetland plant associations of northwestern Oregon Author: Institute for Natural Resources, Christy, John A., Oregon Natural Heritage Information Center This guide provides keys, descriptions, and stand tables for 122 native freshwater plant associations (14 forest and woodland, 28 shrub, 78 herbaceous, 2 nonvascular) in northwestern Oregon, based on analysis of data from 1,992 plots distributed throughout the study area. Descriptions are provided for eight other plant associations for which there are no plot data. Data were also not available for 114 additional associations reported from the study area (Kagan et al. 2000). The study area includes the north half of both the Coast Range and Western Cascade ecoregions, and all of the Willamette Valley. Vegetation is classified according to the National Vegetation Classification System, and plant associations are assigned to ecological systems that are currently being developed on a nationwide level. Title: Native freshwater wetland plant associations of northwestern Oregon Author: Institute for Natural Resources, Christy, John A., Oregon Natural Heritage Information Center This guide provides keys, descriptions, and stand tables for 122 native freshwater plant associations (14 forest and woodland, 28 shrub, 78 herbaceous, 2 nonvascular) in northwestern Oregon, based on analysis of data from 1,992 plots distributed throughout the study area. Descriptions are provided for eight other plant associations for which there are no plot data. Data were also not available for 114 additional associations reported from the study area (Kagan et al. 2000). The study area includes the north half of both the Coast Range and Western Cascade ecoregions, and all of the Willamette Valley. Vegetation is classified according to the National Vegetation Classification System, and plant associations are assigned to ecological systems that are currently being developed on a nationwide level. Close