Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. Growth and wood density traits of individual rings were measured via X-ray densitometry, and relationships of ring density and its...
Recent natural disasters around the world including
both tsunamis and hurricanes, have highlighted the inability
of wood buildings to withstand wave and surge
loading during these extreme events. Little is known
about the interaction between coastal residential light-frame
wood buildings and wave and surge loading because
often little is left...
Wood-plastic composites are generally presumed to be inherently more resistant to moisture uptake than solid wood, but there is little data on the relative rates of moisture uptake in these materials over time. Trex[R] and Strandex[R] deck sections were immersed in water for up to 215 days, then sections were...
Large quantities of smaller diameter materials are available in the overstocked forests of eastern Oregon and Washington, but the costs of removing these materials and the long distances from markets sharply reduce the potential of this resource. Failure to thin these forests will sharply increase the likelihood of catastrophic wildfires....
In a multilevel study to determine limits to underplanted conifer seedling growth, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), grand fir (Abies grandis (Dougl. ex D. Don) Lindl.), western redcedar (Thuja plicata Donn ex D. Don), and western hemlock (Tsuga heterophylla (Raf.) Sarg.) seedlings were planted beneath second-growth Douglas-fir stands that had...
The ratio of live crown length to tree height (crown ratio; CR) is often used as an important predictor variable for tree level growth equations, particularly for multi-species and multi-layered stands. Also, CR indicates tree vigour and can be an important habitat variable. Measurement of CR for each tree can...
From 27 June to 3 September 1999, CO2 fluxes from a 5-year-old, 84.15-ha vegetated clearcut in sub-boreal British Columbia were measured using a Bowen ratio energy balance (BREB) system and a second approach (the component model) that was based on scaled up CO2-flux measurements from belowground and plants (spruce seedlings...
In their recent Canadian Journal of Forest Research Comment 368 article, Wilson and Oliver (2000) developed an equation for predicting the average ratio of height to diameter at breast height for the largest 250 trees/ha (H/DL250) in unthinned stands as a function of initial density and dominant height of the...
Studies on types and impacts of crime have indicated that crime and violent acts do occur on public lands and have negative consequences for managers of those lands and recreation visitors. It is important, then, to evaluate how to reduce or eliminate crime and violent acts on public lands. To...
The ability to treat Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) with oilborne copper-8-quinolinolate or with waterborne chromated copper arsenate, ammoniacal copper zinc arsenate, or ammoniacal copper quaternary was assessed using commercial treatment facilities in the Pacific Northwest. In general, Scots pine was more easily treated than was...
Spatially explicit information on the species composition and structure of forest vegetation is needed at broad spatial scales for natural resource policy analysis and ecological research. We present a method for predictive vegetation mapping that applies direct gradient analysis and nearest-neighbor imputation to ascribe detailed ground attributes of vegetation to...
The potential of 17 hydroxylamine derivatives as wood preservatives was assessed on ponderosa pine sapwood blocks exposed to one of two decay fungi: Gloeophyllum trabeum or Trametes versicolor. Weight losses on untreated controls were generally lower with the white-rot fungus (T. versicolor) averaging 30.4 percent, while those for the brown-rot...
Mold and stain fungi can be easily controlled by kiln-drying, but even this material can be rewetted during shipping and storage, allowing fungi to colonize the wood. The potential for using surface spray treatments with commercial formulations containing combinations of propiconazole, didecyldimethyl ammonium chloride, or 3-iodo-2-propynyl butylcarbamate to protect kiln-dried...
We perform two-dimensional linear elastic finite element analysis to investigate the mechanical stability of ultrathin Ge/Si film grown on or bonded to SiO₂, using imperfect interface elements between Si and SiO₂ to model Si/SiO₂ interfacial slippage. We demonstrate that the overall composite film is stable when only the tangential slippage...
Diameter growth and age data collected from stumps of 505 recently cut old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees at 28 sample locations in western Oregon (U.S.A.) indicated that rapid early and sustained growth of old Douglas-fir trees were extremely important in terms of attaining large diameters at ages 100–300...
Stem sinuosity is a highly visible stem-form trait in the leaders of fast-growing Douglas-fir (Pseudotsuga menziesii var. (Mirb.) Franco) trees, yet its cause is unknown. We tested the hypotheses that sinuous stems have longer expanses of primary growth than nonsinuous stems (putting the leader at higher risk curvature, induction of...
An experiment evaluating three levels of vegetation competition control (no control, 1.5 m2 of vegetation control, and 3.3 m2 of vegetation control), each with two fertilization treatments (fertilization at the time of planting with complete slow-release fertilizer (Woodace® IBDU), or no fertilization), was installed at five sites. Two of these...
The relationships among stand structure, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) branch characteristics, and red alder (Alnus rubra (Bong.)) stem form attributes were explored for 10- to 15-year-old trees growing in mixed Douglas-fir – red alder plantations. Treatments included a range of species proportions, and red alder was either planted simultaneously...
The incidence of treated wood in a recycling stream was assessed at a recycling center in western Oregon. Chromated copper arsenate (CCA) was the predominant treatment present in the material, ranging from 0 to 2 percent of the material present at any given time. Treated wood was present at 38...
Many stands of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) near coastal areas of Oregon and Washington are heavily infected with the foliar pathogen causing Swiss needle cast (SNC) disease, and yet there is very little research on the resulting wood quality. Modulus of elasticity (MOE), modulus of rupture (MOR), microfibril angle...
Mixed conifer and hardwood stands in southwestern Oregon were studied to explore the hypothesis that competition effects on individual-tree growth and survival will differ according to the species comprising the competition measure. Likewise, it was hypothesized that competition measures should extrapolate best if crown-based surrogates are given preference over diameter-based...
A common garden study investigated growth, morphology, and cold hardiness of yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) seedlings originating from seed that had matured at an accelerated rate. This early maturing seed, produced at a low-elevation southern Vancouver Island seed orchard, was known to have similar germinability and seedling morphology...
Genetic control of cold hardiness in two-year-old seedlings was compared with that in 7-year-old saplings of 40 open-pollinated families in each of two breeding populations (Coast and Cascade) of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) from western Oregon. In addition, the efficacy of bud phenology traits as predictors...
The physical demands of rapid and economical running differ from the demands of fighting in ways that may prevent the simultaneous evolution of optimal performance in these two behaviors. Here, we test an hypothesis of functional trade-off in limb bones by measuring mechanical properties of limb bones in two breeds...
This study was designed to measure the microbiological and chemical characteristics of forest soils in a chronosequence of harvested Douglas-fir (Pseusotsuga menziesii (Mirb.) Franco) stands in different climatic settings. Mineral soil samples were collected along transects running from old-growth (OG) forests into harvested stands of ages 5, 15, and 40...
This is the fourth in a series of studies to evaluate perceptions of U.S. Department of Agriculture Forest Service law enforcement personnel of the roles, responsibilities, and issues related to their jobs. An e-mail survey was administered to the 89 Forest Service special agents, assistant special agents in charge, senior...
This study is the second in a series of studies to evaluate perceptions of USDA Forest Service law enforcement personnel of the roles, responsibilities, and issues entailed in their jobs. An e-mail survey was administered to the nine Forest Ser-vice special agents in charge (SACs) across the United States. All...
This is the third in a series of studies to evaluate perceptions of USDA Forest
Service law enforcement personnel of the roles, responsibilities, and issues entailed
in their jobs. An e-mail survey was administered to the 79 Forest Service patrol
captains and patrol commanders (PCs) across the United States. Seventy...
This is the fifth in a series of studies to evaluate perceptions of the roles, responsibilities,
and issues entailed in the jobs of U.S. Department of Agriculture Forest
Service law enforcement and investigations (LEI) personnel. An e-mail survey
was administered to the 537 Forest Service forest supervisors and district rangers...
This study is the first in a series of studies to evaluate perceptions of USDA Forest Service law enforcement personnel of the roles, responsibilities, and issues entailed in their jobs. An email survey was administered to 404 law enforcement officers (LEOs) in national forests across the United States. In all,...
This study quantifies the short-term effects of low-, moderate-, and high-severity fire on carbon pools and fluxes in the Eastern Cascades of Oregon. We surveyed 64 forest stands across four fires that burned 41,000 ha (35%) of the Metolius Watershed in 2002 and 2003, stratifying the landscape by burn severity...
The land area required for a marker-aided selection (MAS) program to break-even (i.e., have equal costs and benefits) was estimated using computer simulation for coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in the Pacific Northwestern United States. We compared the selection efficiency obtained when using an index that included the phenotype...
The 3-PGS (physiological principles for predicting growth using satellite data) model generates monthly estimates of transpiration, photosynthesis, and net primary production (NPP), the latter derived as a fixed proportion (0.47) of gross photosynthesis. To assess the reliability of a simplified process model (3-PGS) to predict the productive capacity of coniferous...
We used a new model, STANDCARB, to examine effects of various treatments on carbon (C) pools in the Pacific Northwest forest sector. Simulation experiments, with five replicates of each treatment, were used to investigate the effects of initial conditions, tree establishment rates, rotation length, tree utilization level, and slash burning...
Little is known of wood properties in trees that were initially suppressed and subsequently released from suppression. The purpose of this study was to assess differences in growth ring width, specific conductivity (Ks), tracheid dimensions, moisture content, and wood density in suppressed Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western hemlock...
Tsunami force and pressure distributions on a rigid
wall fronted by a small seawall were determined experimentally
in a large-scale wave flume. Six different
seawall heights were examined, two of which were exposed
to a range of solitary wave heights. The same
experiment was done without a seawall for comparison....
The potential for moisture sorption by boron and fluoride rods following application of rods to wood to affect subsequent chemical diffusion was investigated in small Douglas-fir blocks conditioned to 30, 60, or 90 percent target moisture content (MC). MCs tended to decline over the 180-day test period, but there was...
The effect of drying conditions on gas permeability and preservative treatability
was assessed on western hemlock lumber. Although there were no differences in gas
permeability between lumber dried at conventional and high temperatures, there were
differences in preservative penetration. High-temperature drying was associated with
improved penetration of ammoniacal copper zinc...
A chronosequence of three species of logs (Pinus sylvestris L., Picea abies (L.) Karst, and Betula pendula Roth.) from northwestern Russia was resampled to develop a new method to estimate rates of biomass, volume, and density loss. We call this resampling of a chronosequence the decomposition-vector method, and it represents...
Decomposition of woody roots in Sitka spruce (Picea sitchensis (Bong.) Carrière), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and ponderosa pine (Pinus ponderosa P. Laws. ex C. Laws.) dominated forests in Oregon, U.S.A. was studied using a chronosequence. Roots of five coniferous species were excavated from stumps with ages up to 46...
We examined the spatial distribution of crime incidents on USDA Forest Service lands using a geographic
information system and several spatial analysis techniques. Our primary objective was to examine
whether patterns existed in the spatial distribution of crime and to explore the relationship of patterns
to other geographic features using...
To assess regional stores of coarse woody debris (CWD) in seven major forest regions of Russia, we combined data collected as part of the routine forest inventory with measurements in 1044 sample plots and the results of density sampling of 922 dead trees. The stores of CWD in the western...
Few studies have examined the own-price elasticity of Canadian softwood lumber supply or output-adjusted factor demand elasticities over the past two decades, despite the utility of these measures in understanding producer response to tariffs, to market shifts (such as the decline in U.S. public harvest), and to changes in domestic...
Using a qualitative approach, the authors tested a crime
typology developed for tourism destinations in a U.S. National
Forest recreation setting. Specific objectives were to
classify the attributes of crime and violence, examine the effects
of crime and violence on visitor demand, and suggest
methods of prevention and recovery. A...
Molds are an increasingly important issue for all building materials, including
wood. While washing with bleach is a commonly recommended method for removing
molds, and the associated discolorations, there is surprisingly little information on the
effectiveness of this treatment. The ability of mold removal treatments to brighten
wood and eliminate...
This is the synthesis of a series of studies to evaluate perceptions of U.S. Department of Agriculture Forest Service (USFS) law enforcement and investigations (LEI). Five groups were evaluated: four groups of employees from different positions within LEI, and a group of customers of LEI, the line officers of the...
Finite element analysis was used to study the effective transverse modulus of solid wood for all possible end-grain patterns. The calculations accounted for cylindrical anisotropy of wood within rectangular specimens and explicitly modeled wood as a composite of earlywood and latewood. The effective modulus was significantly reduced by growth ring...