bluuebunny/crossref_metadata_2025 huggingface dataset:
Productivity and Cost of Partial Harvesting Method to Control Mountain Pine Beetle Infestations in British Columbia
Authors: Han Han-Sup , Renzie Chad
Published: August 2019

Small patch cutting (<1 ha in size) in mature lodgepole pine (Pinus contorta Douglas var. latifolia Engelmann) stands has been introduced in central British Columbia, Canada to slow the spread of mountain pine beetle (Dendroctonus ponderosae Hopk.) populations. This practice is locally referred to as “Snip and Skid” logging. This article addresses the operational challenges of implementing the method, with an emphasis on the cost of each phase of logging. Total stump-to-truck expenses incurred with Snip and Skid logging in each patch at an average of C$17.00/m3 (C$14.98 to C$19.71/m3). However, if one includes other cost allowances, such as overhead and profit for the logging contractor, the overall cost is C$22.28/m3. These costs greatly increase when trees are smaller. Other costs for implementing the Snip and Skid method, such as planning and layout, ground probing, and baiting, further increase the total cost of implementation. Walking and low-bedding, that are not required for typical timber-production logging operations, accounted for 57% of the total delay in Snip and Skid logging. In this particular study, five trees were damaged per 100 m along the skid trails created to access the patches, but we found no high stumps or significant impacts on soils. West. J. Appl. For. 20(2):128–133.
Basal Area and Diameter Distribution Prediction Equations for Young Douglas-Fir Plantations with Hardwood Competition: Coast Ranges
Authors: Knowe Steven A. , Radosevich Steven R. , Shula Robert G.
Published: August 2019

A stand-level modeling system for young Douglas-fir plantations applicable to the Coast Ranges of the Pacific Northwest was developed by using data from 84 growth-monitoring plots. Specific components of the system for predicting current size distributions of planted Douglas-fir include: dominant height and survival of planted Douglas-fir; a basal area projection equation for hardwoods; and diameter distribution percentile prediction functions for planted Douglas-fir. Prediction equations for height, crown width, and height to crown base of individual trees describe stand structure of the planted Douglas-fir. The stand- and tree-level equations include both direct and indirect effects of hardwood competition and site preparation, competition release, and precommercial thinning treatments. With the exception of minimum dbh, stand-level equations for planted Douglas-fir explained at least 92% of the observed variation. Basal area dynamics were simulated through plantation age 20 years for site preparation and competition release treatments of different effectiveness by varying hardwood basal area at plantation age 5 years. The simulations indicate that site preparation must reduce hardwood basal area at plantation age 5 years by 75% or more to realize an increase in Douglas-fir basal area and shift of the diameter distribution toward larger trees. This is due to increased growth of hardwoods that survive site preparation. In contrast, competition release treatments exhibited positive Douglas-fir response with 50% efficacy or more. Therefore, ineffective site preparation treatments need to be followed with competition release treatments having at least 50% efficacy to produce similar Douglas-fir basal area and diameter distributions at age 20 as in stands with no site preparation. West. J. Appl. For. 20(2):77–93.
Survival of the Douglas-Fir Beetle in Peeled and Unpeeled Logs and in Stumps
Authors: Shore Terry L. , Riel William G. , Safranyik Les , Castonguay Julie
Published: August 2019

The Douglas-fir beetle (Dendroctonus pseudotsugae Hopkins) can cause significant mortality to mature Douglas-fir trees (Pseudotsuga menziesii (Mirb.) Franco) during epidemics. Treatment methods are required to reduce local beetle populations to less-damaging levels. We conducted a study to compare the effect on beetle survival of peeling bark from infested logs at two times of year. By Aug., all beetles in bark from logs peeled in July were dead compared with 155.2 beetles/m2 bark in unpeeled logs. In bark from logs peeled at the end of Aug. and left over winter, there were 3.4 beetles/m2 of bark surface compared with 62.3/m2 in unpeeled logs. It was concluded that peeling logs reduces beetle populations, particularly if done early in the summer. We also examined beetle survival in stumps over winter and found that a mean of 70.4 beetles/stump, or 125.6/m2 of stump surface survived winter. It is estimated that it would take beetles emerging from 24 stumps to kill a tree. West. J. Appl. For. 20(3):149–153.
Persistence of Pinyon Pine Snags and Logs in Southwestern Colorado
Authors: Kearns H.S. J. , Jacobi W. R. , Johnson D. W.
Published: August 2019

We examined the persistence of pinyon pine (Pinus edulis Engelm.) standing snags and downed logs in southwestern Colorado pinyon-juniper woodlands. The time since death of pinyon pines killed by bark beetles, black stain root disease, or unknown causes in three study areas in southwestern Colorado was determined through monitoring of permanent plots and dendrochronological crossdating methods. The structural condition and form of the trees was recorded and related to the time since death. Pinyon snags may persist for up to 25 years, with persistence of intact snags averaging 8.4 years and broken snags averaging 13.2 years. Sound logs had been dead for a mean of 9.8 years, whereas more fragmented logs had been dead for a mean of 14.4 years. Extremely fragmented trees had been dead for 16.2 years. There was no statistically significant difference in the time since death for snags versus logs in similar condition classes. A simplified rating system to determine the number of years dead for pinyon pine based on form and condition is provided. West. J. Appl. For. 20(4):247–252.
Evaluation of Risk Assessment of Mountain Pine Beetle Infestations
Authors: Dymond Caren C. , Wulder Michael A. , Shore Terry L. , Nelson Trisalyn , Boots Barry , Riel Bill G.
Published: August 2019

Decision support systems to aid the management of mountain pine beetles combine characteristics of the stand and beetle infestation to estimate risk of damage. Beetle infestation information is now available in a format amenable to the operational implementation of risk. In this study, an established risk rating system was evaluated to determine the utility of the values generated. For a study area located in British Columbia, Canada, global positioning systems were used to survey an infestation. The annual data was used to generate risk for a given year and to compare the ratings with survey data from the subsequent year. Under epidemic conditions, 30% to 43% of the stands rated as high risk were subsequently infested. Of the infested stands, 72% to 76% had a high risk rating. In general, the risk rating system accurately predicted risk in stands that were infested, but not all high risk stands were subsequently attacked. This highlights the difficulty of modeling processes that have a stochastic component. For operational contexts, the estimation of risk on an annual basis is sufficiently reliable to aid in the strategic planning of forest managers.
Douglas-Fir Beetle Response to Artificial Creation of Down Wood in the Oregon Coast Range
Authors: Ross Darrell W. , Hostetler Bruce B. , Johansen John
Published: August 2019

Douglas-fir beetle populations were monitored before and after thinning and felling of trees to create down wood in an 88-year-old Douglas-fir plantation in the Oregon Coast Range. Treatments included an unthinned control, thinning to a target of 75 trees/ha, and thinning to a target of 150 trees/ha. Actual mean tree densities on the plots after thinning were 406, 102, and 154, for the control, 75 trees/ha, and 150 trees/ha treatments, respectively. Fifty trees/ha were felled and left on all thinned plots to create down wood for ecological values. Catches in pheromone-baited traps indicated that the local beetle population increased for 1 year in response to felling and leaving large diameter trees in partial shade. Douglas-fir beetle entrance holes and brood were significantly more abundant on the sides of felled trees and wood borers were significantly more abundant on the upper surface suggesting that treatments that provide maximum exposure of felled trees will create the least favorable habitat for Douglas-fir beetles. However, there were no differences in Douglas-fir beetle entrance holes or brood densities in felled trees between the two thinning intensities. Douglas-fir beetle-caused tree mortality was significantly higher on thinned plots with residual felled trees compared with unthinned controls, although infestation levels were low on all plots (<2 trees/ha). The small increase in beetle-caused tree mortality associated with leaving felled trees would be unlikely to interfere with resource management objectives. These results are applicable to mature, managed forests west of the Cascades with relatively low Douglas-fir beetle populations. In different regions and stand types, or under different environmental conditions, beetle populations could increase to higher densities, remain at high densities longer, and cause higher levels of tree mortality. West. J. Appl. For. 21(3):117–122.
Soil Disturbance and Hill-Slope Sediment Transport After Logging of a Severely Burned Site in Northeastern Oregon
Authors: McIver James D. , McNeil R.
Published: August 2019

Despite considerable public debate in recent years on the practice of postfire logging, few studies have directly evaluated its effects. Soil disturbance and hill-slope sediment transport were measured after a postfire logging operation conducted two years after the 1996 Summit Wildfire (Malheur National Forest), in northeastern Oregon. The wildfire was relatively severe, killing an average of 86% of the trees in experimental units, and leaving an average of 34% mineral soil exposed one year after the fire. Soil disturbance was measured both pre- and postharvest in four replicate units in each of three postfire harvest treatments (unlogged control, commercial harvest [most dead merchantable trees removed], fuel reduction harvest [most dead merchantable trees removed plus most dead trees >10-cm diameter]). There was a significant difference among treatments in the percentage of mechanically disturbed soil area, with an average of 19.4% disturbed in fuel reduction units and 15.2% in commercial units. Displacement (13.7% of soil area), apparent compaction (3.1%), and erosion (0.4%) were the most common types of machine-caused soil disturbance. Controls had significantly less change in mean displacement from pre- to posttreatment compared to fuel reduction units, and significantly less change in erosion compared to commercial units. At the experimental unit level, there was a significant correlation between the number of stems removed and the total amount of mechanical soil disturbance observed. Multiple regressions indicated that logging activity, reflected by the number of stems removed, explained more variation in soil disturbance than relative fire severity, reflected by tree mortality, forest floor mass, or the percentage of mineral soil exposed. There was no correspondence between disturbance within units and hill-slope sediment collected in silt fences below units. Visual inspections and sediment collected in silt fences indicated that little sediment exited the experimental units in the short term, and that the existing road system caused most of the observed hill-slope sediment transport. Low observed levels of sediment transport were likely due to a combination of low-to-moderate slopes, low-to-moderate—risk soils, logging over snow or dry ground, hand felling, no new roads, two years recovery of ground cover between the fire and the logging, problems with measuring hill-slope sediment, and the absence of severe weather events in the two years after postfire logging. Given these mitigating factors, hill-slope sediment transport measured in this study should be considered as representative of the low end of the range that would be expected in a postfire tractor logging operation on similar soils and under similar burn severity conditions. West. J. Appl. For. 21(3):123–133.
Using Airborne Lidar to Discern Age Classes of Cottonwood Trees in a Riparian Area
Authors: Farid A. , Goodrich D.C. , Sorooshian S.
Published: August 2019

Airborne lidar (light detecting and ranging) is a useful tool for probing the structure of forest canopies. Such information is not readily available from other remote sensing methods and is essential for modern forest inventories. In this study, small-footprint lidar data were used to estimate biophysical properties of young, mature, and old cottonwood trees in the San Pedro River basin near Benson, Arizona. The lidar data were acquired in June 2004, using Optech’s 1233 ALTM during flyovers conducted at an altitude of 600 m. Canopy height, crown diameter, stem dbh, canopy cover, and mean intensity of return laser pulses from the canopy surface were estimated for the cottonwood trees from the data. Linear regression models were used to develop equations relating lidar-derived tree characteristics with corresponding field acquired data for each age class of cottonwoods. The lidar estimates show a good degree of correlation with ground-based measurements. This study also shows that other parameters of young, mature, and old cottonwood trees such as height and canopy cover, when derived from lidar, are significantly different (P < 0.05). Additionally, mean crown diameters of mature and young trees are not statistically different at the study site (P = 0.31). The results illustrate the potential of airborne lidar data to differentiate different age classes of cottonwood trees for riparian areas quickly and quantitatively. West. J. Appl. For. 21(3):149–158.
Risk Rating Systems for the Douglas-Fir Beetle in the Interior Western United States
Authors: Dodds Kevin J. , Garman Steven L. , Ross Darrell W.
Published: August 2019

Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, risk rating systems were developed for four USDA Forest Service ranger districts in northern Idaho. Risk rating systems were developed using a geographic information system, USDA Forest Service aerial detection survey maps, and nearest neighbor distances. Years where epidemic populations of DFB occurred over the four ranger districts were selected and risk rating systems were developed for each district. Nearest neighbor distances for between-year (t + 1) and between-2-year (t + 2) infestations were measured. Percentiles of nearest neighbor distances were determined and used to estimate distances at which 50, 75, and 90% of infestations occurred. On average, there was a 50% chance of an infestation occurring within 176 m from previous year infestations, 75% chance from within 517 m, and 90% chance from within 1,188 m. The between-2-year risk rating determined that there is a 50% chance of infestation occurring on average within 249 m, 75% within 627 m, and 90% within 1,332 m from infestations that occurred 2 years earlier. West. J. Appl. For. 21(4):173–177.
Predicting Age of Pinyon and Juniper Using Allometric Relationships
Authors: Gascho Landis Andrew M. , Bailey John D.
Published: August 2019

Management of pinyon-juniper ecosystems often is hampered by insufficient tree age structure data. We developed allometric relationships based on visible and easily measured tree characteristics as tools for predicting tree age. In this study, we tested tree height, diameter at root collar, and crown radius using both single- and multiple-regression analyses to determine which attributes best correlated with tree age. Because soil type and site productivity often affect growth rates of pinyon and juniper, three common soil types in northern Arizona were assessed to determine variation in regression equations. Stepwise regression analysis determined that height and diameter at root collar of juniper were the best variables for predicting age. For pinyon, crown radius on basalt-derived soil and diameter at root collar on limestone-derived soil were the variables of best fit; however, we suggest using diameter at root collar across all sites. We developed models from these allometric relationships to aid in the management of the pinyon-juniper ecosystem.
Role of Foliar Moisture Content in the Silvicultural Management of Forest Fuels
Authors: Keyes Christopher R.
Published: August 2019

In combination with measured stand data and assumed environmental conditions, reasonable estimates of foliar moisture content (FMC) are necessary to determine and justify silvicultural targets for canopy fuels management strategies. FMC often is overlooked in fuels planning, with default values substituting for more precise estimates, but its role is operationally significant in the selection of silvicultural targets even at modest surface fire intensities. This article discusses the role of FMC in canopy ignition and summarizes the results of 11 studies on the FMC values and trends for 16 North American conifers. FMC values ranged from 73 to 480% but varied by species, foliage age, and season. The information presented here will be helpful to managers engaging in canopy fuels planning with the use of popular fire behavior and fuels management software (e.g., NEXUS, Fuels Management Analyst, and the Forest Vegetation Simulator's Fire and Fuels Extension). West. J. Appl. For. 21(4):228–231.
Helicopter Logging Productivity on Harvesting Operations in Southeast Alaska, Using Ecologically Based Silvicultural Prescriptions
Authors: Christian Linda E. , Brackley Allen M.
Published: August 2019

This study examines production rates and costs for felling and helicopter yarding on eight units harvested in accordance with ecologically based silvicultural prescriptions in southeast Alaska. The prescriptions included harvesting to create gaps, harvesting to leave trees in clumps, individual tree selection, and combinations of these treatments. In combination, the treatments represented five levels of basal area (BA) retention. The levels of retention had irregular spatial arrangements caused by gaps and clumps that ranged from 0% retention (clearcut) to 75% of BA retained. Turn time (TT), as adjusted to a standardized distance, and turn weight were used as the basis for estimating productivity. There were statistically significant differences in adjusted TT, depending on the treatment. Areas with higher levels of removal tended to have lower adjusted TTs. With the exception of one unit with a short yarding distance, average turn weights increased as levels of retention decreased. Weighted average cost per thousand board feet (mbf) harvested was $322. The cost per mbf for cutting and yarding together ranged from $305 to $353.
Future Prospects for Private Timber Harvest in Eastern Oregon
Authors: Adams Darius M. , Latta Gregory S.
Published: August 2019

Projections of eastern Oregon private sawtimber harvest are developed using a market model linked to a subplot level projection of growth and inventory. The “base” projection envisions nearly a 50% drop in forest industry harvest relative to recent historical levels, while nonindustrial private forestland harvest remains roughly stable. In this scenario the region would lose nearly one-third of its remaining lumber mills and processing capacity within the first 30 years of the projection. Log prices would show little long-term trend. Simulations of two hypothetical public policies show the impacts of changes in public harvest and the private land base. In a case of expanded riparian protection, which reduces the harvestable private land base by about 11%, private harvest falls by roughly 18% between 2003 and 2033. Large harvest reductions are projected on industrial lands because of limited merchantable inventories. A restoration thinning program on public lands that raises public harvest by 40 million board feet per year over 20 years, sustains recent mill numbers for the next 25 years (although total harvest continues to decline). Substitution of public harvest for private harvest would enable continuation of a higher private cut for several years after the thinning program has ended.
Assessing State-Sponsored Tax Incentive Programs for Nonindustrial Private Forest Landowners in the Western United States
Authors: Eckhoff Mike , Mackes Kurt , Reader Tim
Published: August 2019

In 1982 Colorado approved a constitutional amendment that, in part, provided a lowered property tax rate for agricultural lands. Forested lands were not considered agricultural lands until 10 years later when a statute passed providing for such a consideration, under the Forest Ag program. This new program has created a number of unanticipated consequences, such as increasing stress on county government coffers. This stress may cause the program to be terminated and suggests a need for program reevaluation. As an initial step toward reevaluation, property tax programs affecting nonindustrial private forestland in the western United States were examined. Of the 11 contiguous states, 18 distinct programs were cataloged. Although these programs hold a number of rudimentary features in common, most notably lowering a property owner's tax bill in exchange for land-management activities, further analysis should provide in-depth quantitative analysis.
Monitoring Soil Strength Conditions Resulting from Mechanical Harvesting in Volcanic Ash Soils of Central Oregon
Authors: Parker Robert T.
Published: August 2019

The volcanic ash-derived soils in central Oregon have been shown to compact readily and remain compacted for long periods of time, leading to significant reductions in ponderosa pine (Pinus ponderosa, Laws) tree growth. Concerns over the potential for long-term reduction in forest site productivity on private forestlands in the region led to the development of a soil monitoring process for precisely quantifying changes to the soil environment caused by mechanical harvesting in second-growth ponderosa pine stands. For this study, soil strength was used as an indicator for soil compaction. A recording penetrometer was used to measure soil strength to a depth of 2 ft at intervals of 5 ft along transects established across harvest units. At each sampling point, the number of machine passes was estimated as no disturbance, 1–2 machine passes, 3–5 machine passes, or main skid trails. The penetrometer data were then summarized for each of the four categories. The results show a rapid rise in soil strength with increasing machine activity and 40–70% of the harvest units compacted in a single harvest cycle. The process proved to be an unbiased and practical system for quantifying the extent and intensity of soil strength conditions resulting from mechanical harvesting.
California Logging Utilization: 2004
Authors: Morgan Todd A. , Spoelma Timothy P.
Published: August 2019

Astudy of logging activities conducted during 2004 provided utilization data and information on timber harvesting operations in California. A nested and stratified sampling scheme was used to produce a sample of felled trees with distributions of geographic area, ownership class, tree species, and tree size representative of California's recent sawlog and veneer log harvest. Results of the study indicated that about 50% of the harvested trees were less than 16.5-in.dbh, but these trees produced just 15% of the volume. About 50% of the harvested volume came from trees less than 24.5-in. dbh, and about two-thirds of the volume was from trees less than 30-in. dbh. Removals factors, quantifying impacts on growing stock, revealed that 1,051.4 ft3 of growing-stock volume was removed for every thousand cubic feet delivered to mills, with just 61.5 ft3 left in the forest as logging residue. Periodic reevaluations of logging utilization in California would make it possible to evaluate impacts of technology, market conditions, and policy changes on logging operations and utilization factors in the state.
Prediction of Growth and Mortality of Oregon White Oak in the Pacific Northwest
Authors: Gould Peter J. , Marshall David D. , Harrington Constance A.
Published: August 2019

We developed new equations to predict Oregon white oak (Quercus garryana Dougl. ex Hook.) development within ORGANON, a stand-development model that is widely used in the Pacific Northwest. Tree size, competitive status, crown ratio, and site productivity were statistically significant predictors of growth and mortality. Three scenarios were projected with the new equations, the previous ORGANON model, and the Forest Vegetation Simulator. Compared with the two other models, the new equations predicted greater diameter growth in oak woodland and a greater effect of conifer removal in a conifer-oak stand. The new equations, which are based on considerably more information than previous equations, should give forest managers greater confidence in the ability of ORGANON to estimate the impacts of silvicultural treatments on oaks.
Potentials of Natural Tree Regeneration after Clearcutting in Subalpine Forests
Authors: Kreyling Juergen , Schmiedinger Andreas , Macdonald Ellen , Beiekuhnlein Carl
Published: August 2019

Regeneration of interior mountain forests still is not adequately understood, although these forests are subject to intensified use over the last decades. We examined factors influencing the success of natural tree regeneration after harvesting in the Engelmann spruce–subalpine fir zone of the Monashee Mountains, British Columbia, Canada. Distance from the forest edge was an important factor for regeneration; at distances exceeding 70 m from the forest edge only 50% of plots showed sufficient natural regeneration to meet stocking targets compared with 90% of plots closer to forest edges. Seedling density and growth were superior in the more protected southern portions of clearcuts. Seedling growth was less in plots containing high cover of downed woody debris. There was no relationship between understory plant diversity or composition and tree seedling regeneration. However, cover of fireweed (Epilobium angustifolium) had a significant negative relationship with density but not growth of tree seedlings, particularly for lodgepole pine (Pinus contorta var. latifolia). Cover of fireweed decline substantially within the first 10 years after clearcutting. We conclude that natural regeneration of trees has potential to help achieve stocking targets and also to maintain natural diversity of tree species if spatial constraints, especially thresholds in clearcut size, are considered.
The Effects of Spatial Patterns on the Accuracy of Forest Vegetation Simulator (FVS) Estimates of Forest Canopy Cover
Authors: Christopher Treg A. , Goodburn John M.
Published: August 2019

The Forest Vegetation Simulator (FVS) estimates percent canopy cover without spatially explicit information. Estimates of canopy cover in FVS can be corrected for crown overlap, based on the assumption that trees in a stand are randomly distributed. This research assessed the accuracy of FVS estimates of canopy cover in stands with nonrandom spatial patterns. A method for measuring canopy cover within a geographic information system was developed to compare with FVS estimates of cover for 19, stem-mapped plots across Idaho and Montana. The Ripley's K(d) statistic was used to describe natural and simulated spatial patterns, so that the accuracy of canopy cover estimated by FVS could be considered for groups of plots classified as regular, clustered, or random. Results from the analyses of the effects of spatial patterns indicated that the FVS may underestimate canopy cover by 11% for plots with highly regular spatial patterns and overestimate by 2% for plots with clustered patterns. Although the magnitude of this bias likely is insufficient to justify changing the model's algorithm for canopy cover, users of this model should be aware of the potential bias that can occur as a result of assuming that trees in a stand are randomly distributed. Information on the general spatial pattern of the stand (i.e., clumped, random, and even) could be used by managers to anticipate the expected degree and direction of the bias.
The Impact of Federal and State Income Tax Liabilities on Timber Investments in the West
Authors: Smith Nathan R. , Bailey Phillip , Haney Harry , Salbador Debra , Greene John
Published: August 2019

Federal and state income taxes are calculated for hypothetical forest landowners in two income brackets across 13 states in the West to illustrate the effects of differential state tax treatment. The income tax liability is calculated in a year in which the timber owners harvest $200,000 worth of timber. State income taxes range from highs of $19,693 for middle-income and $34,993 for high-income landowners in Oregon to no income tax in Alaska, Nevada, Washington and Wyoming. After-tax land expectation values for a forest landowner in Oregon are also calculated to illustrate the importance of tax planning on returns to a timber investment. The need for adequate tax accounting is supported by the results.
GuylinePC: An Interactive Guyline Tension Analysis Program for Guyed Logging Towers
Authors: Thompson Matthew , Stander Henk , John Sessions
Published: August 2019

In the US Pacific Northwest and other mountainous regions, cable yarding using portable steel towers is a common harvesting system in steep terrain. These systems are expensive and can be unsafe if improperly rigged. For both economic and safety considerations, configurations are used that ensure that the system can sustain the forces applied during yarding operations. We present a computer-based application, GuylinePC, for evaluating the guyline and anchor loads resulting from an applied load. Our model extends the usability and scope of a model previously developed by other researchers. Specifically we (1) provide a more modern graphical user interface, (2) use optimization methods to determine equilibrium states, and (3) illustrate the capability of the program to be used in design. We briefly discuss the analytical model and software application and present a design problem. The program is intended to improve a forest engineer's understanding of cable yarding systems.
Screening Hydrolyzed Casein as a Deer Repellent for Reforestation Applications
Authors: Kimball Bruce A. , Russell John H. , DeGraan Jeffrey P. , Perry Kelly R.
Published: August 2019

Three independent experiments were conducted to evaluate hydrolyzed casein deer repellent to minimize browse damage in reforestation efforts. In the first experiment, western redcedar seedlings were treated with 12% hydrolyzed casein and a latex sticker or one of two commercial deer repellents in the nursery prior to a 45-day cold storage period. Treated and control (sticker only) seedlings were then offered to captive deer, and browse activity was monitored for 20 days. Whereas all control trees were severely browsed by day 4, the three repellents offered browse protection (17 to 33% survivability at day 20). The second experiment was a field evaluation of 12% hydrolyzed casein, a commercial repellent, and a control. Western redcedar seedlings in nine reforested units were treated and monitored periodically for browse damage by free-ranging deer. After 17 weeks, browse damage to the repellent-treated seedlings (93 and 89% survivability) was significantly lower than the control trees (85%). In the final experiment, three different products were used to affix hydrolyzed casein powder to western redcedar seedlings prior to a 45-day cold storage period. Treated seedlings were offered to captive deer, and browse activity was monitored for 28 days. Hydrolyzed casein–treated seedlings sustained significantly less browse damage (more than 70% survivability at 28 days) versus the controls (all trees browsed by day 28). Nursery treatment with hydrolyzed casein may provide significant protection for conifer seedlings in reforestation operations.
Survival and Sanitation of Dwarf Mistletoe-Infected Ponderosa Pine following Prescribed Underburning
Authors: Conklin David A. , Geils Brian W.
Published: August 2019

We present results on survival of ponderosa pine and reduction in dwarf mistletoe (Arceuthobium) infection after six operational prescribed underburns in New Mexico. Survival 3 years postburn for 1,585 trees fit a logistic relationship with crown scorch, bole char, and mistletoe. The scorch effect was best represented by classes as <90, 90, and 100%; char as char-squared; and mistletoe as DMR < 5, 5, and 6. Survival ranged from over 90% for trees with DMR < 5 and scorch < 90% to almost 0% for trees with DMR 6 and scorch 100%. The proportion of surviving infected trees with reduction in DMR (scorch pruning) increased linearly with scorch. Reductions in average DMR (sanitation) from mortality and scorch pruning were observed on 12 of 14 plots and were associated with average scorch above 25%. A sanitation model estimated DMR reduction of 0.7 with 50% average scorch and initial average DMR of 3.0. Relative risk from scorch, char, mistletoe, and drought for up to 10 years postburn was assessed with proportional hazard models. Results indicate that underburning can be a viable tool to manage dwarf mistletoe, given sufficient fire intensity.
Understory Tree Development with Repeated Stand Density Treatments in Coastal Douglas-Fir Forests of Oregon
Authors: Shatford Jeffrey P.A. , Bailey John D. , Tappeiner John C.
Published: August 2019

We studied the potential for stand density management treatments to increase growth rates of advanced regeneration in the understory of 50- to 70-year-old Douglas-fir (Pseudotsuga menziesii) forests. Study sites in Oregon included a mesic coastal site, a moderate coast range site, and a drier coast range foothills site. Commercial thinning treatments in 1974–1984 led to the establishment of Douglas-fir and western hemlock (Tsuga heterophylla) in the understory and, in 1997, parts of these same stands were thinned for a second time to release this advanced regeneration and promote two-story structure. Both species responded positively where overstory was reduced to 30–40 m2/ha, but western hemlock saplings grew 30–80% more rapidly than Douglas-fir. Average annual height growth of all western hemlock saplings that were more than 1.0 m tall in 1999 was 23–30 cm/year in twice-thinned stands but only 13 cm/year in denser, once-thinned stands. About one-half of all western hemlock saplings doubled or tripled their height in 4 years after a second overstory treatment; the largest 10% of these saplings grew 74–93 cm/year and now represents midstory structure. The response of Douglas-fir saplings to a partial overstory removal was limited. Repeated density management treatments in these Douglas-fir forests can accelerate growth of understory saplings, resulting in the development of two or more canopy layers over time; however, repeated and/or heavy thinning will be required for Douglas-fir sapling growth. Furthermore, because of western hemlock's potential for rapid height growth, some reduction of hemlock sapling density may be needed to maintain vigorous Douglas-fir.
Trembling Aspen Removal Effects on Lodgepole Pine in Southern Interior British Columbia: Ten-Year Results
Authors: Heineman Jean L. , Simard Suzanne W. , Sachs Donald L. , Mather W. Jean
Published: August 2019

Manual cutting treatments are routinely applied to release lodgepole pine (Pinus contorta var. latifolia Engelm.) from trembling aspen (Populus tremuloides Michx.) competition in southern interior British Columbia. We studied the effects of this treatment on pine and an aspen-dominated community on three sites in the Interior Douglas-Fir and Montane Spruce biogeoclimatic zones. After 10 years, when stands were 17–20 years old, treated aspen was significantly shorter than control aspen, and treated pine had significantly (21%) larger diameter than control pine. There were few other differences between brushed and unbrushed pine, and survival was excellent (≥97%), regardless of treatment. Brushing nearly doubled the average density of conifer stems that were free-growing according to legislated standards, but results were variable, and the free-growing status of the stand was changed on only one site. Regression analysis was used to examine the correlation between aspen abundance and pine size. The density of aspen at least as tall as the pine (tall aspen) predicted 36.2% of the variation in pine diameter, and total aspen density predicted 35.9% of the variation in pine height. An average density threshold of 1,867 tall aspen stems/ha, above which pine stem diameter declined, was identified in the three stands.
Naturally Seeded versus Planted Ponderosa Pine Seedlings in Group-Selection Openings
Authors: McDonald Philip M. , Fiddler Gary , Ritchie Martin , Anderson Paula
Published: August 2019

The purpose of this article was to determine whether natural regeneration or planted seedlings should be used in group-selection openings. The answer depends on the survival and growth rate of both types of seedlings, and that could depend on the size of the openings and the effect of trees on their edge. In this side-by-side study, the natural pine seedlings originated from the 1988 seed crop and the 1–0 nursery-grown seedlings were outplanted in spring 1989. Openings ranged from 0.01 to 0.65 ha. The plant community consisted of many species of shrubs, forbs, and grasses with manzanita having the highest density and greatest development. After 9 years, manzanita had an average density of 13,870 plants/ha, 2,050 m2/ha of foliar cover, and was 125 cm tall. From 1990 to 1997, planted ponderosa pine seedlings were taller (P < 0.05) than natural seedlings, and from 1995 to 1997, mean stem diameter at 30 cm of planted seedlings was larger than natural counterparts (P < 0.05). Development for 1 year in the nursery apparently gave the planted seedlings a growth advantage over the natural seedlings. For natural seedlings, distance from opening edge had little effect on pine height or diameter growth regardless of opening size. Planted seedlings, however, appeared to increase in height and diameter growth with both opening size and distance from edge.
Incorporating Regeneration Effort as a Decision Variable in Tactical Harvest Scheduling
Authors: Boston Kevin , Sessions John , Rose Robin , Hoskins Will
Published: August 2019

A variable green-up period is incorporated into a tactical harvest scheduling model to allow for the regeneration policy to be included as a decision variable. The benefit of this formulation was demonstrated by solving a 91-logging unit forest plan under four different green-up policies.The first three policies used fixed green-up periods of 2, 3, and 4 years. The fourth policy uses a variable green-up period where the model selects the regeneration effort that determines the green-up period stand by stand. This policy allows each harvested stand to choose among a 2-, 3-,or 4-year green-up period. The variable green-up period resulted in a slight improvement in the net present value because its total was approximately $3,000 or $1.11/ac higher for the total planning area, not just the harvested acres when compared with the best solutions when 4-, 3-, and 2-year fixed green-up periods were used. The variable green-up constraint adds a level of complexity to the spatial harvest scheduling problem that is easily incorporated into a variety of heuristic procedures because they do not require that all combinations of harvest units be specified before solving the problem. The results cannot be generalized to other forests because the spatial arrangement of the stands is a major component in the value determination. However, using the methodology presented, forest managers can evaluate their own alternatives that may improve the returns from managing their resources.
Using Airborne Light Detection and Ranging (LIDAR) to Characterize Forest Stand Condition on the Kenai Peninsula of Alaska
Authors: Andersen Hans-Erik
Published: August 2019

Airborne laser scanning (also known as light detection and ranging or LIDAR) data were used to estimate three fundamental forest stand condition classes (forest stand size, land cover type, and canopy closure) at 32 Forest Inventory Analysis (FIA) plots distributed over the Kenai Peninsula of Alaska. Individual tree crown segment attributes (height, area, and species type) were derived from the three-dimensional LIDAR point cloud, LIDAR-based canopy height models, and LIDAR return intensity information. The LIDAR-based crown segment and canopy cover information was then used to estimate condition classes at each 10-m grid cell on a 300 × 300-m area surrounding each FIA plot. A quantitative comparison of the LIDAR- and field-based condition classifications at the subplot centers indicates that LIDAR has potential as a useful sampling tool in an operational forest inventory program.
Influence of Ash Substrate Proximity on Growth and Survival of Planted Mixed-Conifer Seedlings
Authors: York Robert A. , Thomas Zachary , Restaino Joseph
Published: August 2019

To address uncertainty in the performance of seedlings planted in and around postburn substrates, we systematically planted seedlings in the center of, on the edge of, and outside ash substrate footprints following burning of logging residue piles and monitored growth and survival for a decade. Five species (Douglas-fir [Pseudotsuga menziesii], giant sequoia [Sequoiadendron giganteum], incense-cedar [Calocedrus decurrens], sugar pine [Pinus lambertiana], and ponderosa pine [Pinus ponderosa]) were planted in a regenerating mixed-conifer stand in the Sierra Nevada range of California. There was a positive effect of ash substrate proximity on growth that was immediate and persisted for 10 years for every species except incense-cedar. Seedlings planted in the centers of ash substrates consistently outgrew (in both height and basal diameter) seedlings that were planted either on the edges of or outside ash substrates. Douglas-fir had the greatest height gain (+47%), followed by giant sequoia (+28%), sugar pine (+23%), and ponderosa pine (+17%). Basal diameter differences were similar. No effect of ash proximity on survival was detected. Planting seedlings in the centers of ash substrates led to exceptionally larger trees by the time the stand had developed enough to apply a precommercial thin, a relevant milestone for managed stands.
Whitebark Pine Planting Guidelines
Authors: McCaughey Ward , Scott Glenda L. , Izlar Kay L.
Published: August 2019

This article incorporates new information into previous whitebark pine guidelines for planting prescriptions. Earlier 2006 guidelines were developed based on review of general literature, research studies, field observations, and standard US Forest Service survival surveys of high-elevation whitebark pine plantations. A recent study of biotic and abiotic factors affecting survival in whitebark pine plantations was conducted to determine survival rates over time and over a wide range of geographic locations. In these revised guidelines, we recommend reducing or avoiding overstory and understory competition, avoiding swales or frost pockets, providing shade and wind protection, protecting seedlings from heavy snow loads and soil movement, providing adequate growing space, avoiding sites with lodgepole or mixing with other tree species, and avoiding planting next to snags.
Small Parcel Fuel Reduction with a Low-Investment, High-Mobility Operation
Authors: DeLasaux Mike J. , Hartsough Bruce R. , Spinelli Raffaele , Magagnotti Natascia
Published: August 2019

Fuel reduction treatments are especially urgent near homes, where a stand replacement fire would also endanger property and human lives. However, the forested properties associated with homes are often too small for cost-effective mechanized fuel treatment performed with traditional methods and equipment. This project tested a small rubber-tracked skid-steer specially modified for forestry operations that can provide all the functions of a complete harvesting system. The skid-steer can, alternately,carry a hot saw for tree felling, a processor to delimb and buck felled trees, a brush cutting head for mastication, and a log-grapple to transport logs and trees. All of the equipment can be transported on a trailer pulled by a heavy pickup truck, which makes for fast, economical movement between project sites. The study confirmed that this system is well suited to small-parcel conditions around home sites and performs best on even terrain, moderate slopes, and softwood trees with a dbh between 5 and 8 in. It took from 7 to 15 productive machine-hours ac−1 to perform all treatment phases (i.e., mastication, felling, processing, and skidding). The occurrence of delays significantly increased this figures, bringing the average 9.7 productive hours ac−1 to 13.5 worksite hours. Treatment cost was estimated at $480 ac−1 and $1,146 ac−1 for whole-tree and cut-to-length harvesting, respectively. In addition to offering a reasonable treatment cost, the system has the advantage of requiring a low investment, which allows small-scale enterprises to get into the business.
Evaluating Satellite Imagery‐Based Land Use Data for Describing Forestland Development in Western Washington
Authors: Kline Jeffrey D. , Moses Alissa , Azuma David , Gray Andrew
Published: August 2019

Forestry professionals are concerned about how forestlands are affected by residential and other development. To address those concerns, researchers must find appropriate data with which to describe and evaluate rates and patterns of forestland development and the impact of development on the management of remaining forestlands. We examine land use data gathered from Landsat imagery for western Washington and evaluate its usefulness for characterizing low-density development of forestland. We evaluate the accuracy of the satellite imagery‐based land use classifications by comparing them with other data from US Forest Service's Forest Inventory and Analysis inventories and the US census. We then use the data to estimate an econometric model describing development as a function of socioeconomic and topographic factors and project future rates of development and forestland loss to 2020. We conclude by discussing how best to meet the land use data needs of researchers, forestry policymakers, and managers.
A Case for Increasing Forest Biomass Utilization Research in Colorado
Authors: Eckhoff Mike , Mackes Kurt
Published: August 2019

Colorado's forests are being squeezed by two intense, seemingly relentless, and largely antagonistic forces. The first force is the increasing pressure from within the forest due to dense, overgrown stands. The second force is the increasing pressures from increasing human populationsexogenous to the forests. One way to improve forest health and reduce risks to humans at the same time is to remove materials in the form of forest biomass from the forest through hazardous fuels reduction projects. Forest biomass can be used in a variety of products, but because of low profitmargins, forest biomass is used for energy purposes only when no other product is possible. However, because of recent policy enactments, energy uses are becoming more attractive. These recent policy enactments are briefly discussed. Then, potential forest biomass uses are considered, includingelectricity generation, thermal applications, and the production of second-generation liquid biofuels. Recommendations are made for uses that stand the best chance of restoring forest health, reducing fire risk to homes, providing a renewable alternative to fossil fuels, and reducing the costsof doing so to taxpayers.