bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stem Taper and Volume of Managed Red Alder
Authors: Hibbs David , Bluhm Andrew , Garber Sean 
Published: August 2019

Abstract
Ataper equation and a volume table are presented for red alder (Alnus rubra Bong.) trees grown in plantations. Fourteen diameter measurements from each of 234 trees were collected from nine plantations throughout the Pacific Northwest. Diameter inside bark (dib) along the stemwas fitted to a variable exponent model form. Individual tree merchantable volume was then estimated as volume inside bark by integrating the taper function from 6 in. (stump height) to the height at a 5-in. (diameter outside bark) top. Incorporating two easily measured tree variables—dbhand total tree height—provided an accurate fit. Model results and the use of an independent evaluation data set of plantation-grown trees indicated that the model presented here was a better predictor of dib in managed stands than previously published red alder taper equations. Thisequation provides reliable dib and merchantable volume predictions and is an improvement over previous red alder volume and taper equations.
Ponderosa Pine Growth Response to Soil Strength in the Volcanic Ash Soils of Central Oregon
Authors: Parker Robert T. , Maguire Douglas A. , Marshall David D. , Cochran Pat 
Published: August 2019

Abstract
Mechanical harvesting and associated logging activities have the capacity to compact soil across large portions of harvest units, but the influences of compaction on long-term site productivity are not well understood. Previous research in central Oregon has shown that volcanic ash soils compact readily under both compression and vibration loads, resulting in long-term alteration in soil density and a decline in tree growth. In this study, soil strength (SS) and tree growth were assessed in areas subject to repeated timber harvesting with the objective of quantifying the relationship between ponderosa pine (Pinus ponderosa Laws.) growth and SS. Two thinning treatments (felled only versus felled and skidded) in 70- to 80-year-old ponderosa pine stands were replicated at three sites in 1991. Subsequent 5-year growth in diameter, height, and volume of residual trees were assessed with respect to SS measured by a recording penetrometer. Felled and skidded plots had 44% higher SS values than felled-only plots (P = 0.05). Although no treatment effect on growth was detected at the plot level, diameter, height, and volume growth of individual trees within plots declined significantly as average SS within a 30-ft zone of influence increased from approximately 800 to 2,500 kPa. Results show the potential use of SS measurements for monitoring impacts of harvesting operations on tree growth.
Larch Seed Trees Sustain Arboreal Lichens and Encourage Recolonization of Regenerating Stands
Authors: Bunnell Fred L. , Goward Trevor , Houde Isabelle , Björk Curtis 
Published: August 2019

Abstract
In many areas Bryoria lichen is a major winter food for deer and caribou. We examined the role of western larch (Larix occidentalis) seed trees in retaining arboreal lichens and encouraging recolonization of regenerating stands by Bryoria. Although exposed to desiccation, Bryoria was sustained in significant amounts in larch seed trees. Other than a reduction near roads, apparently by alkaline road dust, arboreal forage lichens were relatively uniformly distributed throughout the regenerating stands. There was little difference in abundance up to 135 m from the source tree. The sorediate form of the lichens did better on lodgepole pine (Pinus contorta), and larger, nonsorediate fragments were more abundant on western larch. We attribute the difference to bark pH. Scattered western larch seed trees were effective at retaining lichens and facilitating recolonization of the regenerating stand.
Comparing Classification Systems for Ponderosa Pine Snags in Northern Arizona
Authors: Waskiewicz Justin D. , Fulé Peter Z. , Beier Paul 
Published: August 2019

Abstract
The degree to which snag classification systems predict actual snag “age” (time since tree death) is rarely known. We used dendrochronology to determine the death dates of 79 large (more than 40 cm dbh, more than 3 m in height) ponderosa pine snags in northern Arizona and compared the snag ages to those predicted by a commonly used simulation model and to five classification systems. The methods are limited to trees for which intact tree-ring samples could be extracted, but the data provided evidence of some snags standing for long periods (to 141 years) and correlation of snag traits with age. The simulation model underestimated snag age in the first three categories. Mean ages of snags in the last category were estimated accurately but with low precision. Comparison of snag ages to their classification in five systems showed that bole breakage was unrelated to snag age, that limb loss occurs at divergent rates between individual trees, and that wood decay does not necessarily proceed sequentially. A system based on the attrition of bark from snag boles proved useful for distinguishing snags by physical traits, but different classification systems may be needed to meet specific needs for assessing past forest structure and wildlife habitat.
Forest Health Decline in a Central Oregon Mixed-Conifer Forest Revisited After Wildfire: A 25-Year Case Study
Authors: Filip Gregory M. , Maffei Helen , Chadwick Kristen L. 
Published: August 2019

Abstract
A 500-ac mixed-conifer forest near Cache Mountain in central Oregon was examined in 1979, 1992, 2002, 2004, and 2005 to document causes of forest health decline and subsequent wildfire damage. The site is dominated by grand fir (Abies grandis) and ponderosa pine (Pinus ponderosa), with some lodgepole pine (Pinus contorta) and subalpine fir (Abies lasiocarpa). Part of the area was clearcut or shelterwood harvested from 1983 to 1985. Between 1979 and 1992, grand fir increased substantially, whereas ponderosa pine decreased in stems and basal area/ac in the unharvested areas. From 1979 to 2002, grand fir experienced severe mortality that was caused primarily by the root pathogen, Armillaria ostoyae, and the fir engraver (Scolytus ventralis). In 2003, a wildfire burned all of the study area, and by 2004, most of the grand fir, subalpine fir, and lodgepole pine was killed. The least amount of mortality from fire occurred in the larger-diameter ponderosa pine. Two years after the 2003 fire, some of the grand firs with bole or crown scorch that were alive in 2004 were killed by fir engravers by 2005. For ponderosa pines, only a few trees with bole or crown scorch that were alive in 2004 were killed by bark beetles, mostly mountain pine beetle (Dendroctonus ponderosae) and red turpentine beetle (Dendroctonus valens), by 2005. This case study has relevance to current interpretations of forest health in similar mixed-conifer forests, the major causes of forest health decline, and the role of fire in forest health.
Nonhost Angiosperm Volatiles and Verbenone Protect Individual Ponderosa Pines from Attack by Western Pine Beetle and Red Turpentine Beetle (Coleoptera: Curculionidae, Scolytinae)
Authors: Fettig Christopher J. , Dabney Christopher P. , McKelvey Stephen R. , Huber Dezene P.W. 
Published: August 2019

Abstract
Nonhost angiosperm volatiles (NAV) and verbenone were tested for their ability to protect individual ponderosa pines, Pinus ponderosa Dougl. ex. Laws., from attack by western pine beetle (WPB), Dendroctonus brevicomis LeConte, and red turpentine beetle (RTB), Dendroctonus valens LeConte (Coleoptera: Curculionidae, Scolytinae). A combination of (−)-verbenone and eight NAVs [benzyl alcohol, benzaldehyde, guaiacol, nonanal, salicylaldehyde, (E)-2-hexenal, (E)-2-hexen-1-ol, and (Z)-2-hexen-1-ol] (NAVV) significantly reduced the density of WPB attacks and WPB successful attacks on attractant-baited trees. A significantly higher percentage of pitchouts (unsuccessful WPB attacks) occurred on NAVV-treated trees during two of three sample dates. In addition, significantly fewer RTB attacks were observed on NAVV-treated trees during all sampling dates. The application of NAVV to individual ponderosa pines significantly reduced tree mortality, with only 4 of 30 attractant-baited trees dying from bark beetle attack while 50% mortality (15/30) was observed in the untreated, baited control. To our knowledge, this is the first report establishing the effectiveness of NAVs and verbenone for protecting individual ponderosa pines from WPB attack.
Mortality Associated with a Bark Beetle Outbreak in Dwarf Mistletoe-Infested Ponderosa Pine Stands in Arizona
Authors: Kenaley Shawn , Mathiasen Robert , Harner E. James 
Published: August 2019

Abstract
Ponderosa pine (Pinus ponderosa Douglas ex C. Lawson var. scopulorum Engelm.) mortality was evaluated from a 2002 bark beetle outbreak in areas infested with southwestern dwarf mistletoe (Arceuthobium vaginatum [Willd.] Presl subsp. cryptopodum [Engelm.] Hawksw. & Wiens) in a total of nine study sites in northern Arizona. Ponderosa pine mortality attributable to bark beetles (Ips and Dendroctonus spp., Scolytidae) was systematically sampled, and stand attributes, such as basal area, tree density, dwarf mistletoe severity, and site indices were recorded. Ponderosa pine mortality was predominately attributed to Ips spp. Although the prolonged drought likely was the inciting factor responsible for the Ips spp. outbreak, results suggested a strong relationship between ponderosa pine mortality and the interaction between crown class and dwarf mistletoe rating class. Ponderosa pines severely infected with dwarf mistletoe and in the intermediate crown class are at the greatest risk of Ips spp. attack during outbreak years in northern Arizona.
Stability of Herbicide Resistance over 8 Years of Coppice in Field-Grown, Genetically Engineered Poplars
Authors: Li Jingyi , Meilan Richard , Ma Cathleen , Barish Michael , Strauss Steven H. 
Published: August 2019

Abstract
Herbicide resistance may be useful for reducing costs and environmental impacts, and improving yields, during weed control in poplar plantations. However, genetically engineered traits can sometimes show instability, which would compromise their commercial value. To study the stability of herbicide resistance, we analyzed resistance to the contact herbicide glufosinate in 384 transgenic plants originating from 32 gene-insertion events created within two Populus hybrids (P. tremula × P. alba and P. tremula × P. tremuloides). Resistance was measured at the start and end of an 8-year period during which trees were cut and allowed to resprout in the field several times. The transgenic events had widely varying levels of resistance, ranging from complete tolerance to nearly complete sensitivity. When analyzed as three classes (tolerant, intermediate, and sensitive), the levels of resistance remained stable, and there were no cases of resistance breakdown. The level of theresistance-conferring PAT protein, based on enzyme-linked immunosorbent assays, was strongly correlated with resistance class; thus, simple protein assays should enable early screening for acceptable resistance levels. Our data suggest that commercial levels of herbicide resistance and stability can be introduced into elite clones of hybrid poplar with as little as 2–3 years of transformation and field testing.
Horizontal Measurement Performance of Five Mapping-Grade Global Positioning System Receiver Configurations in Several Forested Settings
Authors: Wing Michael G. , Eklund Aaron , John Sessions , Richard Karsky 
Published: August 2019

Abstract
We examined the horizontal measurement performance of five mapping-grade GPS receiver configurations operating simultaneously at three measurement test sites established in open sky, young forest, and closed canopy conditions. Two of the GPS receivers had external antennas, and two receivers were configured to collect data with real-time differential corrections through the Wide Area Augmentation System (WAAS). The GPS receivers collected data using 1-, 30-, and 60-point recording intervals to test the influence of the number of point recordings on position determination. We also postprocessed all data to examine the influence of differential corrections. We found statistically significant differences in measurement accuracy between GPS receiver configurations that had an external antenna and receivers that did not. The top performer for unprocessed data collected measurements with real-time differential corrections and had average measurement errors of 0.4, 0.8, and 2.2 m, in open sky, young forest, and closed canopy conditions, respectively. The top performer for postprocessed data had average measurement errors of 0.2, 0.1, and 1.2 m, in open sky, young forest, and closed canopy conditions, respectively. The influence of number of points on measurement accuracy was observed between the 1- and 30-point intervals, with no statistically significant differences between the 30- and 60-point intervals. No statistically significant difference resulted in WAAS measurements that were postprocessed. The measurement accuracies we report are acceptable for many natural resource measurement applications. These findings encourage the use of external antennas when using GPS receivers under forest canopy. In addition, point recording intervals of 30 appear to be efficient for accurate measurements with mapping-grade GPS receivers.
Wildland—Urban Interface Communities' Response to Post-Fire Salvage Logging
Authors: Ryan Robert L. , Hamin Elisabeth 
Published: August 2019

Abstract
Salvage logging, the removal for profit of standing trees that have been damaged by extensive wildfires, has been quite controversial and subject to lawsuits that can delay the logging past the time in which the lumber is still useful. It has not been clear, however, whether the public that has been most affected by wildfires—those that live near burned areas—support or oppose postfire logging. In this research we use focus groups and stakeholder interviews in urban interface communities that have experienced significant wildfires to examine in some detail the perspectives these members of the public have regarding salvage logging. Public support for salvage logging in communities that have recently experienced wildfires was much stronger than hypothesized at the beginning of this study from our review of the number of unsuccessful salvage logging proposals or even popular press reports. Key reasons for supporting salvage logging were that letting useful timber rot was wasteful, that it improves the postfire aesthetics and safety of the forest, and that it can provide some income for local postfire restoration activities. Caveats include assuring that any environmental impacts, such as new roads, are mitigated postlogging, and assuring that appropriate snags are left to provide wildlife habitat.
The Potential Use of the Light Drop-Weight Deflectometer to Control Subgrade Compaction on Forest Roads
Authors: Boston Kevin , Robek Robert , Rathom Jesse 
Published: August 2019

Abstract
Improving subgrade strength can reduce a road's construction and maintenance costs. Additionally, it may lessen some of the environmental impacts from forest roads. However, most forest roads receive little effort to establish or control compaction because of the perceived increase in construction costs and potential delays in the flow of wood from the area. A light drop-weight deflectometer was tested on two forest roads in western Oregon to determine if this tool could aid with improving forest road construction by improving the quality of the road's subgrade. One road was built on a fine sand-silt soil and the other was constructed on a silt-clay soil. The goal was to correlate the easily collected subgrade values produced from the light drop-weight deflectometer and wet unit weight to the soaked and nonsoaked California bearing ratio (CBR) values for the subgrade, which are common design variables used to determine the minimum thickness of the aggregate surface. The light drop-weight deflectometer showed mixed results with regards to its ability to predict the values from the more expensive CBR laboratory test. The results from site 1, sand-silt soils, showed the potential of the light drop-weight deflectometer to aid in construction control as the values from light drop-weight deflectometer, when combined with the wet unit weight, explained a statistically significant amount of the variability in the soaked and nonsoaked laboratory CBR values. These variables explain approximately 60% of the variation in CBR values. The data from site 2, the silt-clay soils, were not able to significantly predict the subgrade strength variables, and the road will need to continue to use the traditional methods for establishing and controlling compaction.
Thinning Ponderosa Pine Affected by Armillaria Root Disease: 40 Years of Growth and Mortality on an Infected Site in Central Oregon
Authors: Filip Gregory M. , Fitzgerald Stephen A. , Chadwick Kristen L. , Max Timothy A. 
Published: August 2019

Abstract
Portions of a 30-year-old stand of ponderosa pine were precommercially thinned in 1966 and commercially thinned in 2000 at age 64 years to determine the effects of thinning from below on tree growth and mortality caused by Armillaria root disease in central Oregon. Thirty years after precommercial thinning, leave-tree mortality was significantly less in thinned plots than in unthinned plots, but leave-treeߝdiameter growth was not significantly increased by thinning. Leave-tree basal area (BA) per acre growth, however, was significantly greater in thinned plots.In 2007 at age 71 years, 7 years after commercial thinning of the same plots that were precommercially thinned in 1966, leave-tree mortality was less in thinned plots than in unthinned plots, but more time probably is necessary to adequately assess Armillaria-caused mortality after commercial thinning. Both tree diameter and BA growth were significantly increased by commercial thinning. Hypotheses on fungal-host dynamics are discussed, and recommendations for multiple thinning based on stand density index are given.
Fall Planting and Tree Shelters for Reforestation in the East Washington Cascades
Authors: Taylor Michael , Haase Diane L. , Rose Robin L. 
Published: August 2019

Abstract
Reforestation on harsh, high-elevation sites near the crest of the Cascade Mountains in Washington can be challenging because of persistent snowpack and extreme climatic variation. The use of tree shelters was investigated with two species, Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and western larch (Larix occidentalis Nutt.), on two Yakama Nation sites across three fall planting dates. For both species, seedlings inside tree shelters had increased survival compared with nonsheltered seedlings after one growing season despite increased damage by crushing from snowpack. Volumetric soil moisture content on the western larch site increased from 10% to 17% between the first and second planting dates, resulting in no effect of planting date on western larch survival. On the Douglas-fir site, however, soil moisture content was below 12% for all fall planting dates, resulting in only 2% survival for those seedlings planted on the first planting date. First-season seedling growth was unaffected by planting date or tree shelter treatment for both species. These results indicate the critical importance of soil moisture at time of planting and onset of precipitation after planting. Use of tree shelters may improve seedling survival on a harsh, high-elevation site, but it increases potential seedling damage because of crushing by snowpack.
Fuel Supply Planning for Small-Scale Biomass Heating Systems
Authors: Farr Angela K. , Atkins David 
Published: August 2019

Abstract
The Fuels for Schools and Beyond initiative partners have gained experience assisting with installation and fuel supply planning for woody biomass heating systems in six western states. In attempting to use forest management waste or slash that would otherwise be piled and burned, thepartners are promoting changes in currently available biomass systems technology and current forest practices. The many benefits of forest biomass heat can be realized today with careful communication about fuel supply specifications. Guidance based on the partners' experience in fuel supplyplanning and defining fuel specifications is presented.
Growth Response of Pinus ponderosa following a Mixed-Severity Wildfire in the Black Hills, South Dakota
Authors: Keyser Tara L. , Smith Frederick W. , Shepperd Wayne D. 
Published: August 2019

Abstract
In late summer 2000 the Jasper Fire burned ∼34,000 ha of ponderosa pine forest in the Black Hills of South Dakota. Although regarded as a catastrophic event, the Jasper Fire left a mosaic of fire severity across the landscape, with live trees present in areas burned under low andmoderate fire severity. In October 2005, we cored 96 trees from unburned, low-severity, and moderate-severity stands and assessed whether tree growth differed among fire severity classes during the 5 years postfire. We observed no differences in basal area increment (BAI) 10 years prefireamong fire severities with BAI averaging 9.6 cm2 per year. Despite severe drought conditions, BAI in moderate severity sites 2 years postfire was 58% greater than in unburned and low-severity stands. Although significant, this growth increase was short-lived. Three, 4, and 5 yearspostfire, no differences in growth among unburned, low-severity, and moderate-severity sites were detected, as BAI averaged 8.3, 7.5, and 7.0 cm2, respectively. The lack of a consistent and prolonged growth response suggests that the Jasper Fire did not result in any short-termchanges in growth patterns. Data extending beyond 5 years postfire are required to infer potential long-term changes in tree growth and productivity.
The Effects of Forestry Site Preparation on Mountain Beaver Demographics and Associated Damage to Tree Seedlings
Authors: Arjo Wendy 
Published: August 2019

Abstract
Timber resources are a vital part of the economy in the Pacific Northwest, yet reforestation efforts are often hampered by animal damage. Understanding the factors that influence seedling damage can assist managers in implementing appropriate techniques to reduce species-specific damage. I radio-collared and monitored mountain beavers (Aplodontia rufa) from preharvest to seedling planting to determine the impacts of forest management practices on demographics. In addition, I monitored Douglas-fir (Pseudotsuga menziesii) seedlings on 28 plots on two harvest units (Vesta and Schoolhouse) to determine the effects of chemical site preparation on mountain beaver foraging and subsequent seedling damage. Mountain beaver densities differed between silvicultural treatments (F3,39 = 3.58, P < 0.02), although reproductive success did not (χ2 = 0.14, df = 1, P = 0.70). Larger mountain beaver home ranges were documented in the mature timber compared with those following harvest. Home ranges were also larger in the chemical site preparation portion of the unit (mean = 3.37 ± 0.9 ha) than in the nontreated portion of the unit (mean = 0.82 ± 0.17 ha) on Vesta. Herbicide treatment did not promote seedling damage on either unit. Vegetation does not appear to be the only factor influencing mountain beaver movements and seedling damage. Availability of water is very important for mountain beavers and may also influence their foraging choice, as well as contributing to their increased movements in mature timber (reduced groundwater) versus clearcut areas. Understanding the effects of vegetation on population demographics and subsequent seedling damage may allow for initiating a nonlethal management method using alternative forage.