bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stocking Control Procedures for Multiaged Ponderosa Pine Stands in the Inland Northwest
Authors: O'Hara Kevin L. , Valappil Narayanan I. , Nagel Linda M. 
Published: August 2019

Abstract
Multi-aged management of forest stands in western North America is a viable option in many areas where traditional even-aged management is undesirable. Procedures for guiding stocking control for multi-aged ponderosa pine (Pinus ponderosa) stands were developed using the PP-MASAM model (Ponderosa Pine–Multi-aged Stocking Assessment Model). These procedures allow the user to divide stands into components such as age classes or canopy strata that are the basic unit for growing space allocation. Growing space is represented by leaf area index. Stocking regimes are assessed over a single cutting cycle through projections of volume increment, stand density, and tree vigor. The approach is flexible for guiding stocking in ponderosa pine stands for diverse structural objectives including retention of ancient trees, development of presettlement structures, stands with two to four age classes, or stands with short or long cutting cycles. Example stocking regimes and internet links are provided to access the model. West. J. Appl. For. 18(1):5–14.
Applying Logistic Regression to Determine Regeneration Risk to Stand Replacement Fire on the Kootenai National Forest, Montana
Authors: Hall Wendy L. , Zuuring Hans R. , Hardy Colin C. , Wakimoto Ronald H. 
Published: August 2019

Abstract
In 1994, fire managers on the Kootenai National Forest observed that wildfires had produced regeneration loss in some stands but not in others. They questioned what site characteristics and management activities were related to this loss. To address this question and to establish guidelines to “triage” stands and prioritize management efforts, we applied a logistic regression model to data from a set of regeneration stands (n = 135) located on the Libby, Rexford, and Three Rivers Ranger Districts. The occurrence of a stand replacement fire was modeled as a logistic function of Aspect, Habitat Type, Fuel Treatment, and logarithm of trees/ac (log_TPA), with R2 = 0.523 (P < 0.05). Odds ratios derived from logistic regression identified the descriptor characterizing regeneration stands “most at risk” for a stand replacement fire and provided a means to triage stands. Southwest and south aspects had the highest odds ratios (22 and 9) and largest coefficients of variation (3.07 and 2.22) for the Aspect variable. Western hemlock/queencup beadlilly (Tsuga heterophylla/Clintonia uniflora) and western red-cedar/queencup beadlilly (Thuja plicata/Clintonia uniflora), with respective odds ratios of 30 and 17, had the largest coefficients of variation (3.40 and 2.83) for the Habitat Type variable. For the Fuel Treatment variable, the “no fuel treatment” category had the highest odds ratio (11) and coefficient of variation (2.38). Stands with stand replacement fire had a mean log_TPA significantly lower than that of non-stand replacement fire stands (P < 0.001). Competition from understory vegetation may explain these findings. Bracken fern (Pteridium aquilinum), commonly found in cedar-hemlock stands and on southerly aspects, may outcompete tree seedlings and provide a fine-fuel hazard. West. J. Appl. For. 18(3):155–162.
Environmental Effects and Economics of Mechanized Logging for Fuel Reduction in Northeastern Oregon Mixed-Conifer Stands
Authors: McIver J.D. , Adams P.W. , Doyal J.A. , Drews E.S. , Hartsough B.R. , Kellogg L.D. , Niwa C.G. , Ottmar R. , Peck R. , Taratoot M. , Torgersen T. , Youngblood A. 
Published: August 2019

Abstract
Fuel reduction by mechanical thinning and removal was studied in mixed-conifer stands in northeastern Oregon between 1995 and 1997. A single-grip harvester was coupled with either a forwarder or a skyline yarding system, and operational economics, fuel reduction, stand damage, soil disturbance, effects on soil biota and down-woody material were measured in three replicates of paired stands. After logging with the harvester, the two log-extraction systems achieved nearly equivalent fuel reduction with 45.7 and 46.8% mass reduction by the forwarder and skyline system, respectively. Fine-woody fuel increased slightly in all units, but mass of heavy fuels decreased. Most mass reduction in the forest floor occurred in the duff layer with 56 and 49% reduction in forwarder and skyline units, respectively. Reduction in stem density and basal area were similar for the two extraction systems; in forwarder units stem density was reduced by 61.6% and basal area by 55.4%, while in skyline units stem density was reduced by 66.5% and basal area by 51.1%. Of seedlings and trees examined, 32% had noticeable damage after harvest. Damage included bole wounding (38.9% of damaged stems), bark scraping (35.0%), wrenched stems (28.9%), broken branches (26.5%), broken terminal leaders (15.4%), and crushed foliage (4.1%). More damage occurred to residual large trees than to seedlings. Both log-extraction systems met the silvicultural prescription of reducing fuel and protecting residual large-diameter western larch, Engelmann spruce, Douglas-fir, and lodgepole pine. While fuel, stem, and basal area reduction lowered fire risk from a model 10 to a model 8 in all stands, large-woody material for wildlife also changed. Mean log length was lower in harvested units relative to unharvested controls, but this did not decrease occupation of logs by ants or the activities of woodpeckers feeding on them. Of 37 logged hectares, 1.4% (0.5 ha) of the soil area was compacted, mostly in forwarder units, within landings, and within trails close to landings. The percent area with displaced soil varied from 5 to 43% among units and was located within trails or in intertrail areas between the trails. Light displacement of soil resulted in a short-term increase in the abundance of soil microarthropods. The effects of compaction on litter microarthropods was more persistent, with lower numbers in compacted litter a year after harvest. While revenue was similar for forwarder and skyline units ($68 vs. $70/metric ton, respectively), total operational costs were $81/metric ton in the skyline units, compared to $46/metric ton in the forwarder units. These results are discussed in the context of options available to managers for balancing fuel reduction needs with both environmental and economic constraints. West. J. Appl. For. 18(4):238–249.
Hybrid Poplar in the Willamette Valley
Authors: Hibbs David , Withrow-Robinson Brad , Brown Dina , Fletcher Rick 
Published: August 2019

Abstract
Hybrid poplar (Populus spp.) is the newest tree crop in the Pacific Northwest. We have been studying its management and growth in the Willamette Valley of western Oregon on poorly drained soils with no irrigation. We found very good growth rates—up to 4000 ft3/ac in 6 yr—on soils considered poor for many kinds of agriculture. For plantation establishment, we found that after 1 yr, simple no-till methods were as effective as the often-used ripping and tilling approaches. An herbicide screening study resulted in good poplar growth with some herbicides and reduced growth with two others commonly used in site preparation. Our investigation of root development indicates that the good growth on these poorly drained, nonirrigated soils is associated with poplar's deep and extensive root development. West. J. Appl. For. 18(4):281–285.
An Application of LiDAR in a Double-Sample Forest Inventory
Authors: Parker Robert C. , Evans David L. 
Published: August 2019

Abstract
Multireturn LiDAR data (2-m posting) were used in a double-sample forest inventory in central Idaho. Twenty-four 15-plot (0.2 ac) strips were established with a real-time Differential Global Positioning System. Tree dbh and height were measured on every 5th plot. Volume and basal area were computed for eight encountered species. LiDAR trees were selected with a focal max filter and height computed as the z-difference between interpolated canopy and DEM surfaces. LiDAR-derived trees/ac, height, and dbh had mean differences of −4.4 trees, −10.7 ft, and −1.01 in. from ground values. Four dbh-height models were fitted. Predicted dbh was used to compute LiDAR estimates of basal area and volume on 360 Phase 1 plots. Phase 2 LiDAR estimates on 60 plots were computed by randomly assigning heights to species classes using a 500-iteration Monte Carlo simulation. Regression estimators for Phase 2 ground and LiDAR ft3 and ft2 were computed by single and composite species. Phase 1 estimates were partitioned to obtain species volumes. The regression estimate of composite volume was partitioned by percent species distribution of trees, basal area, and volume. There was no statistical difference between individual and partitioned composite species estimates. Sampling error was ±11.5% on a mean volume estimate of 1,246 ft3/ac with standard error ±72.98 ft3/ac. West. J. Appl. For. 19(2):95–101.
Minimizing the Cost of Stand Level Management for Older Forest Structure in Western Oregon
Authors: Latta Greg , Montgomery Claire A. 
Published: August 2019

Abstract
The area of old-growth forest in the Pacific Northwest is estimated to have declined dramatically from historical levels. Active management involving repeated thinning that leaves substantially fewer trees than a typical commercial thin has been proposed as a way to speed the development of older forest structure in the region. This study uses a random search heuristic and an individual tree simulation model, ORGANON, to search for cost-effective old forest management regimes for a wide range of stand types that occur on private land in western Oregon. The regimes were designed to meet older forest structural criteria, as defined by the Oregon Department of Forestry, for 30 years prior to clearcut harvest. The opportunity cost of managing for older forest structure was estimated for each stand type as the value of forgone timber production under maximum net present value management. Opportunity cost was found to be positively correlated with site quality, stand age, and stocking. Cost-effective management for older forest structure is important because the lower the cost of conservation, the more likely it will occur. West. J. Appl. For. 19(4):221–231.
Largest-Crown-Width Prediction Models for 53 Species in the Western United States
Authors: Bechtold William A. 
Published: August 2019

Abstract
The mean crown diameters of stand-grown trees 5.0-in. dbh and larger were modeled as a function of stem diameter, live-crown ratio, stand-level basal area, latitude, longitude, elevation, and Hopkins bioclimatic index for 53 tree species in the western United States. Stem diameter was statistically significant in all models, and a quadratic term for stem diameter was required for some species. Crown ratio and/or Hopkins index also improved the models for most species. A term for stand-level basal area was not generally needed but did yield some minor improvement for a few species. Coefficients of variation from the regression solutions ranged from 17 to 33%, and model R2 ranged from 0.15 to 0.85. Simpler models, based solely on stem diameter, are also presented. West. J. Appl. For. 19(4):245–251.
Equations for Predicting Uncompacted Crown Ratio Based on Compacted Crown Ratio and Tree Attributes
Authors: Azuma David , Monleon Vicente J. , Gedney Donald 
Published: August 2019

Abstract
Equations to predict uncompacted crown ratio as a function of compacted crown ratio, tree diameter, and tree height are developed for the main tree species in Oregon, Washington, and California using data from the Forest Health Monitoring Program, USDA Forest Service. The uncompacted crown ratio was modeled with a logistic function and fitted using weighted, nonlinear regression. The models were evaluated using cross-validation. Mean squared error of predicted uncompacted crown ratio was between 0.1 and 0.15, overall bias was negligible, and correlation between the predicted and observed uncompacted crown ratio was high for most species. The sensitivity of crown fire risk to crown ratio estimation method was evaluated using the Fire and Fuels Extension of the Forest Vegetation Simulator. Torching index, an estimate of the wind speed needed for a crown fire to develop, was significantly greater when compacted crown ratio was used instead of uncompacted crown ratio. The close agreement in torching indices simulated using predicted and observed uncompacted crown ratio provides further evidence of the utility of the models developed in this study. West. J. Appl. For. 19(4):260–267.
A Sustained-Yield Scheme for Old-Growth Douglas-fir
Authors: Newton Michael , Cole Elizebeth C. 
Published: August 2019

Abstract
From analysis of two Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands, 120 and 140 years old, we conclude that managed stands can meet established criteria for old-growth Douglas-fir and simultaneously produce near-maximum yields of good-quality timber. With the management approach outlined here, average annual volume growth may approach that of shorter-rotation culture, but in logs of a size and quality normally found only in older stands, and with minimal impact on high-risk watersheds or old-growth habitat. This possibility encourages development of silvicultural systems that can achieve such goals in a variety of timber types. West. J. Appl. For. 2:22-25, Jan. 1987.
Spatial Relationship of a Wildfire, Fuelbreaks, and Recently Burned Areas1
Authors: Salazar Lucy A. , González-Cabán Armando 
Published: August 2019

Abstract
The Wheeler Fire #2 on the Los Padres National Forest, California, burned over 118,000 ac (47,755 ha) in 2 weeks. Several weather and physical factors contributed to the large size of this fire: drought conditions, high temperatures, erratic winds, low humidity, steep topography, poor access, and continuous stands of chaparral. This fire presented the rare opportunity for evaluating the coincidence of a wildfire, fuelbreaks, and recently burned areas. Observations indicate that the spatial relationships of fuelbreaks, roads, prescribed burns, and wildfires are important determinants of fire behavior and growth, and they merit special consideration in fuels and fire management planning. More case study documentation would provide fire managers with valuable information for developing guidelines on how to approach similar problems, under the same or different conditions. West. J. Appl. For. 2(2):55-58, April 1987.
Silvicultural Approaches to Develop Northern Spotted Owl Nesting Sites, Central Coast Ranges, Oregon
Authors: Andrews Lawrence S. , Perkins John P. , Thrailkill James A. , Poage Nathan J. , Tappeiner II John C. 
Published: August 2019

Abstract
The life-history requirements of northern spotted owls (Strix occidentalis caurina), a federally listed “threatened” species, are associated with late-successional habitats. Nesting sites are an important habitat requirement for spotted owls. We used an individual-tree, distance-independent growth model to explore a range of management scenarios for young Douglas-fir stands (age class 50 years) and estimated which scenarios promoted the development of forest patches that emulate the species mix and diameter distributions at known spotted owl nest sites in the central Coast Ranges of Oregon. Our modeling indicates that without silvicultural intervention or natural disturbances, the young stands (170–247 trees/ac) investigated did not develop features associated with spotted owl nest sites within 160-year total stand age. Silvicultural simulations that modeled heavy thinnings at ages 50 and 80 years, followed by tree-planting and additional thinnings developed forest patches structurally similar to our sample of spotted owl nest sites. We infer that silvicultural activities in federally managed, late-successional reserves may need to include alternatives beyond the scope of those permitted under current land use guidelines to accelerate the development of stand structures that better meet the nesting site requirements of spotted owls. West. J. Appl. For. 20(1):13–27.
Observer Variation in Tree Diameter Measurements
Authors: Elzinga Caryl , Shearer Raymond C. , Elzinga Glenn 
Published: August 2019

Abstract
Tree diameter breast height (dbh) was measured on 879 permanently marked trees by two experienced professional foresters. Error rates were approximately equal between observers. Measurement error rates of 5% of tree diameter or greater may be expected in dbh measurements on as many as 5% of measured trees. West. J. Appl. For. 20(2):134–137.
Washington State's Forest Regulations: Family Forest Owners' Understanding and Opinions
Authors: Creighton Janean H. , Baumgartner David M. 
Published: August 2019

Abstract
Washington State has one of the most restrictive sets of Forest Practice Rules (FPR) in the United States. In 1974, the Washington State legislature passed the Forest Practice Act, with the intent of improving environmental conditions by regulating forest practices such as road building, harvesting methods, and the use of chemicals. We found that a knowledge gap exists within the private forest landowner community in Washington State with regards to some state and federal environmental regulations. The larger-acreage landowners with longer ownership tenures were more familiar with forest regulations than were the newer smaller-acreage landowners, based on a survey conducted in 2002. Regardless of regulation familiarity, a substantial number of respondents expressed concern over the limits placed on their ability to manage their lands as they see fit. This sentiment does not seem to arise purely from the potential for economic loss, because timber does not appear to be an important component of respondent incomes. Rather, the loss of management control and government restrictions placed on private property rights may be more significant. Agencies responsible for enforcing these regulations need to recognize that changes are taking place in the greater forest landowner community, and that the approaches of the past may no longer be appropriate for the future. West. J. Appl. For. 20(3):192–198.
Predicting the Availability of Understory Structural Features Important for Canadian Lynx Denning Habitat on Managed Lands in Northeastern Washington Lynx Ranges
Authors: Gilbert Brian A. , Pierce Wade 
Published: August 2019

Abstract
Stands identified as potential Canadian lynx denning habitat by a habitat suitability model were sampled in northeastern Washington for stand structure and understory structural features identified as important for denning lynx. Potential den structures were quantified by use of strip transects, and stand structure was quantified through an enhanced forest inventory approach focused on assessing understory and downed wood conditions. Information theoretic model selection methods indicated that the best model to predict potential denning understory structure availability included downed wood abundance, total basal area, and average stand diameter. The strong predictive ability of our models suggest that understory features important to denning lynx can be predicted using traditional inventory data with the addition of a downed wood line intercept methodology. In general, our study supports the suggestion that assessing downed wood availability will effectively address concerns over quantifying the availability of understory structural features identified as being important at lynx den sites. West. J. Appl. For. 20(4):224–227.
Long-Term Seedfall, Establishment, Survival, and Growth of Natural and Planted Ponderosa Pine in the Colorado Front Range
Authors: Shepperd Wayne D. , Edminster Carleton B. , Mata Stephen A. 
Published: August 2019

Abstract
Seedfall, natural regeneration establishment, and growth of planted seedlings was observed from 1981 to 2001 under shelterwood and seedtree overstories in a replicated study in ponderosa pine in the Manitou Experimental Forest in the Colorado Front Range. Good seed crops were produced only every 4 to 6 years, with almost no viable seed produced in intervening years. With seed predation, only 14% of total seedfall was available for germination. Shelterwood overstories containing between 6 and 14 m2 ha−1 stem basal area over scarified seedbeds provided optimal conditions for natural seedling establishment. Survival and growth of planted seedlings was much better than that of natural seedlings. However, poor survival and slow initial growth may require many years to establish a fully stocked forest of natural seedlings.
Evacuation Behavior during Wildfires: Results of Three Case Studies
Authors: Cohn Patricia J. , Carroll Matthew S. , Kumagai Yoshitaka 
Published: August 2019

Abstract
Evacuation of rural communities threatened by wildfires is occurring more often, particularly in the western United States. Residents, public safety officials, community leaders, and public land managers are facing the issues and problems of this new experience. We used semi-structured interviews to elicit the evacuation experience from the viewpoint of evacuees and public safety officials in three case studies of wildfire evacuations in the western United States during 2000 and 2002. (Our interviews were conducted only with Teller County residents and officials.) We identify and describe the stages of the evacuation process as experienced by evacuees, and the dynamics and dilemmas associated with each stage. We analyze these perceptions and dynamics using the sociological lenses of social construction of meaning and structuration. The results indicate that evacuees and public safety officials have different perceptions and concerns about the evacuation process. We derive lessons learned from these three cases for use in planning future wildfire evacuations.
Plant Species Diversity in Young Conifer Plantations in Northern and Central California
Authors: McDonald Philip M. , Fiddler Gary O. 
Published: August 2019

Abstract
In this age of ecosystem management, plant species have value as an integral component of an ecosystem, as possible sustenance for animals, and even as a provider of medicines or food for humans. Plant species in plantations are no exception. But what species are present, how long are they present, and does their number increase or decrease? Are some species found in most plantations? Such knowledge could enhance the management of vegetation in plantations as well. In 21 study areas (plantations) in northern and central California with at least 10 years of data, we found 237 species in six categories (conifers, hardwoods, shrubs, forbs, graminoids, ferns). The average number of species in each plantation was 23 at the beginning of the studies and 28 after 10 years. The range of species was 13 to 61, with high variability and no trend of species richness to site productivity or age of vegetation. Three species and 10 genera were common to a majority of plantations. The vegetation manager now has some knowledge about species composition in young plantations in northern and central California and how it changes during the first 10 years after site preparation and release.
Site Index Curves for White Fir in the Southwestern United States Developed Using a Guide Curve Method
Authors: Mathiasen Robert L. , Olsen William K. , Edminster Carleton B. 
Published: August 2019

Abstract
Site index curves for white fir (Abies concolor) in Arizona, New Mexico, and southwestern Colorado were developed using height-age measurements and an estimated guide curve and 95% confidence intervals for individual predictions. The curves were developed using height-age data for 1,048 white firs from 263 study sites distributed across eight national forests. These site index curves can be used with standard inventory data for estimating potential site productivity for white fir in the southwestern United States.