We sought to improve net ecosystem exchange (NEE) estimates for a tall, dense, mature Douglas-Fir forest in the Oregon Coast range characterized by weak flows, systematic wind directional shear, and limited turbulent mixing throughout the diurnal period. We used eddy covariance (EC) observations at two levels and concurrent biological measurements...
Dynamics of dead wood, a key component of forest structure, are not well described for mixed-severity fire regimes with widely varying fire intervals. A prominent form of such variation is when two stand-replacing fires occur in rapid succession, commonly termed an early-seral “reburn.” These events are thought to strongly influence...
Wood shear walls are the main lateral force-resisting system for wood-frame construction. Water intrusion and subsequent decay around connections can significantly impact shear wall behavior, but these problems are seldom studied. In this study, effects of water intrusion and fungal attack on shear wall capacity were examined using small-scale (610-...
We present a systems modeling approach to the development of a place-based ecohydrological model. The conceptual model is calibrated to a variety of existing observations, taken in watershed 10 (WS10) at the HJ Andrews Experimental Forest (HJA) in Oregon, USA, a long term ecological research (LTER) site with a long...
The potential for preservative migration from treated wood exposed in or above aquatic environments has become a major concern in some parts of the United States. Best management practices (BMP) were designed to decrease the potential environmental footprint of treated wood, but there are few studies assessing the efficacy of...
Although there is acute concern that insect-caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand-scale simulations or individual events. This study investigates landscape- and regional-scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
The potential for using pretreatment with cinnamon leaf oil or juniper foliage oil to improve the durability of viscoelastic thermal compression (VTC)–treated hybrid poplar was explored in a field termite test and a laboratory mold test. The addition of oils prior to VTC processing had variable effects on resistance to...
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...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Although there is acute concern that insect‐caused tree mortality increases the likelihood or severity of subsequent wildfire, previous studies have been mixed, with findings typically based on stand‐scale simulations or individual events. This study investigates landscape‐ and regional‐scale wildfire likelihood following outbreaks of the two most prevalent native insect pests...
Keywords: Pro School, Western Oregon, vegetation, ecology, hydrology, surveying, Eastern Oregon, Jim Kiser, watersheds, harvesting, Department of Forest Engineering, Resources & Management, Forestry Field School, regeneration
Kalapuya is described as a new, monotypic truffle genus in the Morchellaceae known only from the Pacific northwestern United States. Its relationship to other hypogeous genera within Morchellaceae is explored by phylogenetic analysis of the ribosomal LSU and EF1α protein coding region. The type species, K. brunnea, occurs in Douglas-fir...
Snags (standing dead trees) are an essential structural component of forests. Because wildlife use of snags depends on size and decay stage, snag density estimation without any information about snag quality attributes is of little value for wildlife management decision makers. Little work has been done to develop models that...
Various methods have been used to estimate the amount of above ground forest biomass across landscapes and to create biomass maps for specific stands or pixels across ownership or project areas. Without an accurate estimation method, land managers might end up with incorrect biomass estimate maps, which could lead them...
Port Orford cedar (Chamaecyparis lawsoniana) has a reputation for being resistant to fungal attack, but much of the work to support this premise used older growth material (80-100 yr old). Given the tendency for the heartwood from the second growth of some species to be less durable, we evaluated the...
Routine inspection of wood utility poles to detect internal decay involves drilling holes at or about the ground line. While these holes are useful for detecting internal decay, their presence raises concern among engineers about their potential effects on pole flexural properties. The effect of inspection holes on flexural properties...
The objective of this study was to test a method under development for assigning allowable properties to foreign species graded by American Lumber Standard machine-stress-rated (MSR) rules. The method was tested on dahurian larch (Larix dahurica), a major softwood species that grows in the Russian Far East and could be...
KEYWORDS: Cindy Glick, Eric White, Institude for Working Forest Landscapes, Emily Jane Davis, Thomas Maness, Forest service, Sweet Home Ranger District
Worldwide measurements of nearly 130C3 species covering all major plant functional types are analysed in conjunction with model simulations to determine the effects of mesophyll conductance (gm) on photosynthetic parameters and their relationships estimated from A/Ci curves. We find that an assumption of infinite gm results in up to 75%...
Both the structure and composition of naturally generated early-seral forests in the Pacific Northwest (PNW) can be profoundly different than that of more developed forest seres, especially in the period after a major disturbance but before conifers re-develop a closed canopy. While it is reasonable to suggest that the unique...
Stream temperatures were monitored on seven low-elevation western Oregon streams immediately after clearcut harvesting and 14-17 years later in two studies that examined buffer designs. One study on four streams used no-tree buffers with all trees next to the stream harvested within the clearcut units. The second study on three...
Model–data comparisons of plant physiological processes provide an understanding of mechanisms underlying vegetation responses to climate. We simulated the physiology of a pi~non pine–juniper woodland (Pinus edulis–Juniperus monosperma) that experienced mortality during a 5 yr precipitation-reduction experiment, allowing a framework with which to examine our knowledge of drought-induced tree mortality....
The forest products industry has faced numerous challenges in remaining innovative: outside forces such as industry culture and policy provide few incentives while poor communication among industry actors impedes creative growth from within. This article outlines results gathered from personal interviews with industry professionals and an industry survey on key...
As global climate changes over the next century, forest productivity is expected to change as well. Using PRISM climate and productivity data measured on a grid of 3356 plots, we developed a simultaneous autoregressive (SAR) model to estimate the impacts of climate change on potential productivity of Pacific Northwest (PNW)...
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...
Factors influencing soil organic matter (SOM) stabilization and dissolved organic carbon (DOC) content in complex terrain, where vegetation, climate, and topography vary over the scale of a few meters, are not well understood. We examined the spatial correlations of lidar and geographic information system-derived landscape topography, empirically measured soil characteristics,...
Surface energy balance is a major determinant of land surface temperature and the Earth's climate. To date, there is no approach that can produce effective, physically consistent, global and multi-decadal energy–water flux data over land. Net radiation (R[subscript n]) can be quantified regionally using satellite retrievals of surface reflectance and...
Hybrid poplar (Populus deltoides × Populus trichocarpa) and Douglas-fir (Pseudotsuga menziesii) wood specimens were densified with three variations of Thermo-Hydro-Mechanical (THM) treatment. The THM treatments differed in the steam environment, including transient steam (TS), saturated steam (SS), and saturated steam with 1 minute post-heat-treatment at 200°C (SS+PHT). The bending properties,...
The performance of full-scale light-frame wood walls subjected to wave loading was examined using the Large Wave Flume of the Network for Earthquake Engineering (NEES) Tsunami Facility at Oregon State University. The hydrodynamic conditions (water level and bore speed) and structural response (horizontal force, pressure, and deflection) were observed for...
Components of biodiversity in intensively managed forest stands may be reduced in comparison to naturally regenerated stands. Use of herbicides to suppress herbaceous and woody plant species that compete with planted seedlings has been implicated in negative impacts. We designed a large-scale experimental study to test the influence of intensive...
Many protected areas or parks in developing countries have buffer zones at their
boundaries to achieve the dual goals of protecting park resources and providing
resource benefits to neighbouring people. Despite the prevalence of these zoning
policies, few behavioural models of people’s buffer zone use inform the sizing and
management...
Understanding canopy radiation regimes is critical to successfully modeling vegetation growth and function.
For instance, the vertical distribution of photosynthetically active radiation (PAR) affects vegetation growth,
informative upon carbon and energy cycling. Availing upon advances in information capture and computing
power, geometrically explicit modeling of forest structure becomes increasingly possible....
The Mongolian Steppe is one of the largest remaining grassland ecosystems. Recent studies have reported widespread
decline of vegetation across the steppe and about 70% of this ecosystem is now considered degraded. Among
the scientific community there has been an active debate about whether the observed degradation is related to...
A procedure has been developed to optimize designs of metal-clad post-frame buildings using an expert system. The novel part of the study is the development of a procedure that extends the solution of an engineering problem from a conventional algorithmic Computer Aided Design (CAD) program to be used by the...
Metal-plate-connected wood trusses with semi-rigid joints were investigated by the matrix method of structural analysis. The element-stiffness matrix and fixed-end forces of an individual member with one or both ends semi-rigid were derived as modifications of the idealized cases. The case of unequal elastic connections at two ends of a...
A commercially available, three-dimensional finite-element analysis software was used to model the load-displacement
behavior of metal-plate-connected (MPC) joints in wooden trusses. Model features included consideration
of material properties, teeth-to-grain-to-direction-of-force orientation, wood-to-wood interaction, and gaps between wood
members. To simulate wood-to-plate interaction, the main feature of the model, each tooth of...
A previously developed, three-dimensional (3-D) finite-element (FE) joint model and several two-dimensional
(2-D), beam-element based FE models with different joint-stiffness assumptions (pinned, rigid, and semi-rigid) were used
to analyze the full-scale behavior of a metal-plate-connected (MPC) wood scissors truss. The truss displacement and
force results were investigated for sensitivity with...
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....