Download or read book Structural Development of Late Successional Forests in the Central Oregon Coast Range written by Barbara A. Schrader and published by . This book was released on 1998 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Patterns of western hemlock regeneration were studied in relation to forest structural development and environment in the Oregon Coast Range. Density of western hemlock seedlings was examined across the climatic gradient from cool, moist coastal areas to the seasonally hot and dry Willamette Valley Margin. Seedling densities were most strongly related to stand-level variables including stand age, frequency and abundance of overstory western hemlock trees, abundance of coarse woody debris, decreasing shrub cover, and increasing overstory conifer cover. Significant regional climate and topographic variables included mean annual temperature, precipitation and elevation. Dispersal distances between western hemlock seedlings and potential parents were characterized by measuring distances between seedlings and potential parents. Cone production in western hemlock trees by size class was estimated in four late successional Coast Range stands. Dispersal distances were most commonly short - generally within 10 meters of the nearest potential parent tree. Cone production was related to diameter and crown position, with larger codominant and dominant trees producing more cones than smaller trees. Dynamics and age structure of western hemlock in late successional forests was described in terms of age and size distributions, rooting patterns, and growth rates of western hemlock seedlings, saplings, and trees across the climatic gradient and related to stand level factors in six late successional forests. Time between initial and subsequent western hemlock regeneration pulses varied between 40-70 years. These patterns were observed in all stands. Striking differences in substrate colonization patterns were observed between seedlings and trees and at climatic extremes. Seedlings were predominantly observed on decaying wood while trees were generally observed on forest floor substrates. An exception to this pattern occurred in near-coastal sites where western hemlock of all size classes were found almost entirely on decaying wood substrates. Growth rates across size classes were also calculated and related to regional and stand-level variables. Highest growth rates occurred in low elevation coastal sites, in stands containing the highest levels of coarse woody debris, and the highest level of canopy gaps. Seedling growth rates averaged 4 cm/year for seedlings, and between .2-.6 cm/year diameter growth for overstory saplings and trees.
Download or read book Characteristics of Remnant Old Growth Forests in the Northern Coast Range of Oregon and Comparison to Surrounding Landscapes written by Andrew N. Gray and published by DIANE Publishing. This book was released on 2011-05 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt: Old-growth forests provide unique habitat features and landscape functions compared to younger stands. The goals of many forest mgmt. plans in the Pacific NW include increasing the area of late-successional and old-growth forests. This study describes existing old-growth forests in the northern Oregon Coast Range that might serve as examples of desired future conditions and developmental pathways. Results suggest that although old-growth forests can develop along multiple pathways, stand composition and productivity constrain development such that expecting all late-successional stands to have the full complement of old-growth attributes may not be realistic. Illustrations. This is a print on demand report.
Download or read book Watershed scale Vegetation Patterns in a Late successional Forest Landscape in the Oregon Coast Range written by Michael C. Wimberly and published by . This book was released on 1999 with total page 356 pages. Available in PDF, EPUB and Kindle. Book excerpt: Knowledge about vegetation patterns and ecological processes in unmanaged, late-successional watersheds is needed to provide a foundation for forest management strategies aimed at conserving native biodiversity. I examined influences of environmental variability and disturbance history on forest structure and composition in the Cummins Creek Wilderness, located on the central Oregon coast. Climatic and topographic variables explained the majority of hillslope community composition, while fire history explained most of the variability in hillslope forest structure. Forest structure and composition in riparian areas was related to a climatic gradient as well as position in the stream network. The abundance of two fire-sensitive species, Tsuga heterophylla (western hemlock) and Picea sitchensis (Sitka spruce), decreased with distance from old-growth patches, possibly reflecting a seed dispersal gradient that occurred following fires 80 to 140 years ago. I developed predictive maps of understory conifer patterns using remote sensing, aerial photographs, digital elevation models and stream maps. I predicted P. sitchensis regeneration based on distance from the coast and topography, and T. heterophylla regeneration based on crown size, percent hardwood composition, topography, and distance from old-growth patches. Although I found statistically significant relationships between understory patterns and GIS predictor variables, the models explained only low to moderate amounts of the overall variability. Landscape-scale simulations of T. heterophylla showed that population expansion through gap-phase recruitment was limited by short seed dispersal distances in closed-canopy forests, the requirement for canopy gap disturbances to facilitate overstory recruitment, and the lag between recruitment and reproduction. Although fine-scale habitat features can influence the amount of regeneration in a gap when seed sources are present, the fire regime may ultimately control the abundance of T. heterophylla at the landscape scale through dispersal limitations. Brief increases in fire frequency can cause a sustained decrease in the amount of T. heterophylla on the landscape once fire frequency is reduced below a threshold value. Our results emphasize the complexity and diversity of forest vegetation at the watershed scale. Environmental variability, disturbance history, and dispersal limitations have all played a role in creating the current landscape patterns in the Cummins Creek Wilderness.
Download or read book Characteristics of Remnant Old Growth Forests in the Northern Coast Range of Oregon and Comparison to Surrounding Landscapes written by United States Department of Agriculture and published by CreateSpace. This book was released on 2015-02-14 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt: Old-growth forests provide unique habitat features and landscape functions compared to younger stands. The goals of many forest management plans in the Pacific Northwest include increasing the area of late-successional and old-growth forests. The goal of this study was to describe existing old-growth forests in the northern Oregon Coast Range that might serve as examples of desired future conditions and developmental pathways. In addition, the abundance of specific stand attributes associated with old-growth stands was estimated from regional inventory data. Most of the old-growth stands had experienced moderately severe disturbances during their development resulting in mid- and understory trees belonging to cohorts younger than those of overstory trees. Most of the stands had the full complement of old-growth attributes (large shade-intolerant trees, shadetolerant trees, snags, and down wood), although the dead wood attributes tended to be less abundant in drier stand types. Thresholds for at least four of the five old-growth attributes were met on 7 percent of the inventory plots on federal lands, but on only 0.4 percent of the inventory plots on nonfederal lands. Shade-intolerant trees in particular were low in abundance in mature stands of intermediate diameter class (10 to 30 in). Large-diameter class stands (>30 in) were more abundant near the coast than near the Willamette Valley margin. Results suggest that although old-growth forests can develop along multiple pathways, stand composition and productivity constrain development such that expecting all late-successional stands to have the full complement of old-growth attributes may not be realistic.
Download or read book Comparison of Stand Development of a Deciduous dominated Riparian Forest and a Coniferous dominated Riparian Forest in the Oregon Coast Range written by Nathan Jeremy Poage and published by . This book was released on 1994 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Riparian forests in the central Oregon Coast Range vary along a coniferous-deciduous compositional continuum. Variations in structure and composition affect water quality, fish and wildlife, biodiversity, timber, and aesthetics. A retrospective approach was taken in this study in order to understand and compare the structure, pattern, and history of an unmanaged, mature, deciduous-dominated riparian forest and an unmanaged, mature, coniferous-dominated riparian forest in the central Oregon Coast Range. Information on forest structure and pattern was acquired by mapping locations of all trees and snags (DBH 5cm) within a 2.0 ha and a 2.25 ha reference stand. The history of each stand was reconstructed through analyses of stand structure and composition, tree ages, spatial patterns of trees and snags, as well as detailed field observations. The structure and composition of the two forests is very different. Non-random patterns of trees and snags were observed at multiple scales. Although it is not possible to infer directly the process(es) responsible for observed patterns, point-pattern analysis is a useful tool to detect and describe intra- and interspecific patterns. Neither forest resulted from a single, stand-replacing fire. Instead, both sites were at least partially burned about 145 years ago, possibly in the same fire(s) which spread across an estimated 500,000 acres between the Siuslaw and Siletz Rivers in the mid-1800's (Morris 1934). There is good evidence to suggest that a second fire occurred at the coniferous-dominated site. One or two other fires may have occurred at the deciduous-dominated site. Evidence of wind, herbivory, flooding, pathogens, mass movement events, and non-stand replacing fire was observed at one or both of the sites. Seed source availability as affected by disturbance history may have played a role in forest development at both sites. The seed source availability of red alder relative to Douglas-fir may have increased with successive disturbance events at the deciduous-dominated, riparian forest. A local source of western hemlock seed may have been a key factor in the development of the coniferous-dominated, riparian forest.
Download or read book Northwest Forest Plan Research Synthesis written by and published by . This book was released on 2001 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Forest and Stream Management in the Oregon Coast Range written by Stephen D. Hobbs and published by . This book was released on 2002 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: This major volume presents a wealth of fundamental and applied research on managing Coast Range forest and stream ecosystems. Written primarily for managers and resource specialists, the book will also appeal to policymakers, resource scientists, forest landowners, the conservation community, and students interested in forestry, fisheries, and wildlife sciences.
Download or read book General Technical Report PNW GTR written by and published by . This book was released on 2001 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Location Composition and Structure of Old growth Forests of the Oregon Coast Range written by Glenn Patrick Juday and published by . This book was released on 1976 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Upper Siuslaw Late successional Reserve Restoration Plan Lane and Douglas Counties written by and published by . This book was released on 2004 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Case Studies in Bayesian Statistics written by Constantine Gatsonis and published by Springer. This book was released on 2018-08-17 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains invited case studies with the accompanying discussion as well as contributed papers selected by a refereeing process of 6th Workshop on Case Studies in Bayesian Statistics was held at the Carnegie Mellon University in October, 2001.
Download or read book Managing for Biodiversity in Young Douglas fir Forests of Western Oregon written by and published by . This book was released on 2002 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Integrating Landscape Ecology Into Natural Resource Management written by Jianguo Liu and published by Cambridge University Press. This book was released on 2002-08 with total page 520 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rapidly increasing global population has dramatically increased the demands for natural resources and has caused significant changes in quantity and quality of natural resources. To achieve sustainable resource management, it is essential to obtain insightful guidance from emerging disciplines such as landscape ecology. This text addresses the links between landscape ecology and natural resource management. These links are discussed in the context of various landscape types, a diverse set of resources and a wide range of management issues. A large number of landscape ecology concepts, principles and methods are introduced. Critical reviews of past management practices and a number of case studies are presented. This text provides many guidelines for managing natural resources from a landscape perspective and offers useful suggestions for landscape ecologists to carry out research relevant to natural resource management. In addition, it will be an ideal supplemental text for graduate and advanced undergraduate ecology courses.
Download or read book Oregon Coast Range Province Effectiveness Monitoring Pilot Study written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Silviculture from the Cradle of Forestry to Ecosystem Management written by and published by . This book was released on 1994 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparing Structure and Development of Douglas fir Old growth Plantations and Young Natural Forests in Western Oregon written by Christopher D. Dowling and published by . This book was released on 2003 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ages, diameter growth, density, tree size, and species were studied in old-growth, plantation, and young natural Douglas-fir stands in three areas in western Oregon: the western and eastern Coast Range and the western Cascades. The purpose was to compare the development of these three stand types and to determine whether plantations and young natural stands would develop old-growth structures and characteristics. The Douglas-fir age ranges in plantations (8 to 15 yr) were much narrower and than the ranges of tree ages found in the young natural (21 to 102 yr) and in the old-growth stands (300 to 354 yr). This wide range of tree ages, along with diameter growth rates and tree and stand structural characteristics, supported the hypothesis that old-growth developed at low initial stand densities. These low initial stand densities, probably the result of prolonged stand establishment, likely enabled height and crown size advantages among old and younger trees. Dominant and large codominant trees maintained live crown ratios and sustained diameter growth resulting in large stable trees indicated by low height-to-diameter ratios. The mean diameters of the dominant trees in the old-growth and the dominant trees in the young natural stands were not significantly different at age 40 and 100, indicating the young natural stands appear to be growing at the same rates as the old-growth in its first 100 years. The mean dominant diameters in the plantations and old-growth at age 40 and 100 were significantly different, indicating the plantations are growing and developing differently than young natural and old-growth forests. Plantations had grown rapidly for the first 20 to 30 years, and computer simulation indicated that a significant rapid decline in radial growth would occur between ages 30 and 55. Simulations also indicate that during this period, the mean diameters of the dominant plantation trees would fall below those of the old-growth in two of the three stands by age 85. Pre-commercial thinning 20 to 25 years ago in the plantations has helped sustain high early growth rates for a longer period of time than would have occurred if thinning had not been performed. Additional thinning in the future is likely needed to maintain rapid current rates. When simulated to age 250 both the young natural stands and the plantations maintained higher densities of smaller diameter trees than the old-growth stands. This simulation result indicates the possible inability of these stands to self-thin to the densities found in old-growth stands without some sort of density-reducing disturbance. The broad range of tree ages in the old-growth stands suggests that stand disturbances are a normal part of old-growth development on these sites. Five different plantation thinning options were also simulated to age 250, including additional options with thinning of understory trees and ingrowth. The projections indicate that when the plantations are left unthinned they would generally develop trees with small live crowns and mean diameters but still produce stable dominant overstory trees (low H:D ratios). Shade tolerant understory trees and ingrowth, such as western hemlock, are a key part of old-growth development. These trees may reduce the rate of growth and alter crown structure of the overstory trees over extended periods of time (200+ years). Additional thinning, possibly in multiple entries, in both the overstory and understory may be necessary for dense plantations to develop the tree size heterogeneity found in local old-growth forests. I also demonstrated a methodology to determine site-specific management targets or goals for creating old-growth structure from plantations. This was performed using past and current forest structure and composition information within a local landscape scale of 500 to 1000 acres, typical of the public land checkerboard ownership pattern. Stand types making up the historical landscape are identified and described retrospectively using historical and current aerial photographs and digital orthophotos, cruise records, previous studies, and sample plots of standing and harvested forests. The degree of detail provided through this methodology will likely help forest managers to define complex late-successional characteristics of stands and landscapes. My results indicate that stand and project area-specific definitions of old-growth and clearly defined goals for young stand management will facilitate development of old forest characteristics.
Download or read book Silviculture written by Louise H. Foley and published by DIANE Publishing. This book was released on 1998-07 with total page 265 pages. Available in PDF, EPUB and Kindle. Book excerpt:
