bluuebunny/crossref_metadata_2025 huggingface dataset:
Damage to Residual Trees and Advance Regeneration from Skyline and Forwarder Yarding in Mixed-Conifer Stands of Northeastern Oregon
Authors: Youngblood Andrew
Published: August 2019

Reducing the risk of occurrence of wildfire and outbreaks of insects and diseases through fuel reduction is a priority management objective on federal lands within the Blue Mountains in northeastern Oregon. Optimal methods to achieve desired levels of fuel in mixed conifer stands by mechanical means are as yet unknown. One factor essential in evaluating optimal fuel reduction methods is the damage to residual trees and advance regeneration associated with specific combinations of stand condition, prescription, and harvesting system. Residual stem damage on 12,899 stems was compared after partial cutting and yarding with either skyline or ground-based forwarder in mixed conifer stands of northeastern Oregon. There were 6,092 occurrences of damage on 4,074 stems after yarding; 4.1% of the damaged stems had crushed foliage, 15.4% had a broken terminal leader, 26.5% had broken branches, 28.9% were wrenched, 35.0% had scraped bark, and 38.9% had bole scars. Fir (Abies grandis and A. lasiocarpa) seedlings were more frequently damaged than nonfir (Larix occidentalis, Picea engelmannii, and Pinus contorta) seedlings, and the most frequent damage to fir seedlings occurred in units treated by the forwarder. More damage occurred to residual large trees during yarding than to seedlings. Forwarder yarding resulted in slightly more damage to trees than did skyline yarding. Wrenching was generally consistent between residual seedlings and trees. Scarring occurred more frequently to residual trees than to seedlings. Mean scar area per tree on those actually scarred was generally about 40 cm² on seedlings and 256 cm² on residual trees. Despite slight differences in stand damage, both yarding methods met the silviculture prescription of reducing fuel and protecting large western latch, Engelmann spruce, Douglas-fir, and lodgepole pine stems targeted for retention. This suggests that the decision by resource managers to use one method of yarding over the other should probably be based on considerations such as availability of equipment, costs, and soil impacts. West. J. Appl. For. 15(2):101-107.
Inoculum Reduction Measures to Control Armillaria Root Disease in a Severely Infested Stand of Ponderosa Pine in South-Central Washington: 20 Year Results
Authors: Roth Lewis F. , Shaw Charles G. , Rolph Leonard
Published: August 2019

A stand of ponderosa pine (Pinus ponderosa) severely impacted by Armillaria root disease was treated with five different levels of sanitation by root removal in an attempt to reduce losses to root disease in the regenerating stand. Treatments included: (1) Trees pushed out, maximum removal of roots by machine, visible remaining roots picked out by hand; (2) Trees pushed out, maximum removal of roots by machine; (3) Trees pushed out, no further removal of roots; (4) Trees pushed out, large stumps left, otherwise maximum removal of roots by machine; (5) Clear logged, sod scalped between the stumps, stumps retained. After 20 yr there was a general reduction in mortality with improved sanitation, although treatment #3 was less effective than expected. In each type of stand regeneration (thinned, unthinned, and planted), only treatment #1 consistently expressed less mortality than the other treatments, and differences were significant in the thinned and unthinned portions of the experiment between treatments #1 and #5. Crop tree height and diameter growth after 20 yr were also best in treatment #1. These results do not necessarily indicate that push-over logging is ineffective, but rather they show that after trees and intact stumps have been pushed out, further cleaning is needed to reach the satisfactory sanitation level achieved in treatment #1. Hand cleaning as done in treatment #1 would certainly be cost prohibitive, but perhaps that level of root removal could be achieved in light textured soils with judicious use of a land-clearing brush rake. West. J. Appl. For. 15(2):92-100.
Effectiveness of Repeated Manual Cutting and Glyphosate for Release of Engelmann Spruce from Mixed-Shrub Herb Vegetation
Authors: Comeau P. G. , Biring B. S. , Harper G. J.
Published: August 2019

This study, initiated in 1992, examined the effectiveness of repeated cutting for controlling vegetation in a mixed-shrub-herb community to release planted Engelmann spruce (Picea engelmannii) seedlings. Eight treatments were compared: (a) cut once in spring of 1992, (b) cut once in summer of 1992, (c) 3 yr of cutting once annually in the spring (mid to late June) starting in 1992, (d) 3 yr of cutting once annually in the summer (late July) starting in 1992, (e) 3 yr of cutting twice annually, in the spring and in the summer starting in 1992, (f) 2 yr of cutting twice annually, in the spring and in the summer starting in 1993, (g) application of glyphosate herbicide at 2.1 kg ai/ha during late August, 1992, and (h) an untreated control. Treatments were replicated 3 times in 30 × 30 m plots. Glyphosate treatment (g) and spring cutting treatments (c, e, and J) significantly reduced vegetation (vascular plant) cover and height compared to the control in 1993 and 1994. There were no significant differences in vegetation cover among treatments in year 5 (1996), but vegetation height was significantly lower in the glyphosate treatment (g) and repeated cutting treatments (c, d, e, and f) compared to the control. After 5 yr, spruce survival was high for both control (86%) and treated (> 91%) plots, with no significant (P ≤ 0.05) differences detected among treatments. Repeated cutting treatments (c, d, e, and f) and glyphosate treatment (g) significantly increased root collar diameter (rcd) over that of untreated (h) seedlings, and repeated summer cutting (d) significantly increased seedling height. Three years of repeated cutting (c, d, and e) increased rcd by 54%, and glyphosate (g) increased rcd by 46% compared to the control (h). At the end of year 5, seedlings receiving 3 yr of cutting (e) were not significantly larger than seedlings receiving only 2 yr of cutting (J). West. J. Appl. For. 15(3):154-162.
Can Selection Thinning Convert Even-Age Douglas-Fir Stands to Uneven-Age Structures?
Authors: Miller Mark , Emmingham Bill
Published: August 2019

Uneven-age management of Douglas-fir (Pseudotsuga menziesii) stands can be used to address aesthetic, wildlife habitat, biodiversity, and sustainability concerns, but there has been little long-term experience with this type of management. To develop timely information on converting even-age stands to uneven-age forests, we used retrospective stand reconstruction methods to document harvest frequency, intensity, and stand structural development at four sites in western Oregon. We studied stands managed by selection thinning and identified strategies for creating and managing uneven-age forests. Selection thinning benefited mid- and understory trees and stimulated natural regeneration. Although stand growth was less than expected from low thinning, growth per unit of growing stock was similar to that in unmanaged stands. Douglas-fir often dominated regeneration and had satisfactory vigor at stocking levels about half that considered full stocking for even-age management, but good growth of regeneration may require even lower overstory stocking. Shade-tolerant grand fir and western hemlock, however, were more abundant at higher stocking levels. Selection thinning of young Douglas-fir stands can sometimes be effective in promoting viable regeneration while providing regular income and biodiversity. Because this was a retrospective study only, further, long-term testing is necessary. West. J. Appl. For. 16(1):35–43.
Quantifying Stand Targets for Silvicultural Prevention of Crown Fires
Authors: Keyes Christopher R. , O'Hara Kevin L.
Published: August 2019

Forest managers are expressing a growing interest in proactively reducing susceptibility to crown fires, but the quantitative basis for defining specific stand targets and prescribing silvicultural regimes for this objective is lacking. A procedure is presented for creating resistant stand structures that exploits the relationship between crown fire development and characteristics of stand structure. The BEHAVE surface fire model was integrated with modified versions of the Van Wagner crown ignition and crown fire spread equations in order to quantify structural targets for mitigative silvicultural practices. The procedure tolerates an array of input data types for weather, site, and surface fuel variables so that hazard-reducing guidelines are tailored to specific site and stand conditions. Suggested strategies for achieving crown fire-resistant stand targets include pruning, low thinning, and surface fuel management. West. J. Appl. For. 17(2):101–109.
Views of Old Forestry and New Among Reference Groups in the Pacific Northwest
Authors: Ribe Robert G. , Matteson Mollie Y.
Published: August 2019

A public opinion survey was conducted in Washington and Oregon. It was not a representative poll sample but instead sampled groups of people favoring forest production, those favoring forest protection, and others not aligned with either of these viewpoints. There is strong consensus across groups regarding the unpopularity of established forestry methods and the need to regulate clearcutting. The weight of the sampled groups' opinions indicated that replanting and hiding clearcuts are not enough to make them acceptable, that New Forestry should not be practiced in old growth, and that foresters should attend more to wildlife. There was no clear weight of opinion that forest harvests be eliminated or clearcutting be banned. There was passionate distrust of foresters among many protectionists and nonaligned respondents, but most of the same people support New Forestry intentions. New Forestry offers a potentially more politically acceptable and stable basis for public forestry practice and policy. West. J. Appl. For. 17(4):173–182.
Stocking Control Procedures for Multiaged Lodgepole Pine Stands in the Northern Rocky Mountains
Authors: O'Hara Kevin L. , Kollenberg Cassandra L.
Published: August 2019

Patterns of leaf area distribution in multiaged lodgepole pine stands were used to develop a stocking control model. This model, the Lodgepole Pine–Multi-aged Stocking Control Model (LPP–MASAM), allows the user to design multiaged stand structures for implementation in lodgepole pine stands in the northern Rocky Mountains. The model is suitable for designing stands with two or three age classes, or two canopy strata. These multiaged stands represent a management alternative to even-aged stands where vigorous stands exist and windthrow is not a major constraint. The model requires 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 using projections of volume increment, stand density and tree vigor. Example stocking regimes are provided as are internet links to access the model. West. J. Appl. For. 18(1):15–21.
Marking Tree Seeds with Spray Paint for Germination Studies
Authors: Dumroese R. Kasten
Published: August 2019

I evaluated the potential use of spray paint for marking conifer seeds for germination studies in forest nurseries. For bulk seedlots of large-seeded species like western white pine (Pinus monticola), ponderosa pine (Pinus ponderosa), and Douglas-fir (Pseudotsuga menziesii), paint had little or no effect on six different germination parameters, but negatively affected germination of western larch (Larix occidentalis). On a family level with pine seeds, spray paint may or may not be appropriate depending on the specific objectives of the researcher and the level of conservatism used. West. J. Appl. For. 18(3):175–178.
Eccentricity and Fluting in Young—Growth Western Hemlock in Oregon
Authors: Singleton Ryan , DeBell Dean S. , Marshall David D. , Gartner Barbara L.
Published: August 2019

Stem irregularities can influence estimates of tree and stand attributes, efficiency of manufacturing processes, and quality of wood products. Eccentricity and fluting were characterized in young, managed western hemlock stands in the Oregon Coast Range. Sixty-one trees were selected from pure western hemlock stands across a range of age, site, and densities. The trees were felled and disks were removed from breast height, base of live crown, and various percentage-of-height locations along the bole. Indices of out-of roundness (OOR), pith-off-center (POC), and fluting severity (fluting index) were computed, flutes were counted, and depth of deepest flute was measured on each disk. These variables were related to relative tree height, tree diameter, and several stand- and tree-level attributes. The lower portions of stems tended to be more out-of-round and have a higher degree of off-centered piths than upper stem heights. Basal and breast-height disks had a higher number of flutes, deeper flutes, and higher fluting severity compared to disks from upper stem positions. Tree size (diameter at 4.5 ft) was only weakly correlated with OOR and uncorrelated with POC, but strongly correlated with more flutes, deeper flutes, and higher fluting severity. OOR and POC were not significantly correlated with any other tree or stand attributes. The fluting variables were positively correlated with stand age and overall tree growth rate and negatively correlated with trees/ac. Thus, silvicultural practices that result in more rapid growth, wider spacing, and longer rotations are likely to result in more extensive fluting but will have little or no effect on stem eccentricity. West. J. Appl. For.18(4):221–228.
Hybrid Poplar Genotype Affects Attack Incidence by the Poplar-and-Willow Borer (Cryptorhynchus lapathi)
Authors: Johnson J.D. , Johnson K.R.
Published: August 2019

Increasing incidence of the poplar-and-willow borer (Cryptorhynchus lapathi) in Pacific Northwest hybrid poplar plantations has resulted in reduced wood quality and stem breakage. Three replicated, 5-yr-old clone trials established in the vicinity of Pullman, WA were rated for host attack preference. Attacks by C. lapathi were found to be significant for plantation, clone, and the clone by plantation interaction. Attack rating among clones was affected by genotype. Those clones possessing P. nigra parentage, including Lombardy poplar, OP-367, and PC-6, showed significantly lower attacks across all plantations. Within the P. trichocarpa × P. deltoides (TD) hybrids, both 58-280 and 50-194 consistently exhibited lower attacks compared to the remaining four TD hybrids. Plantation, clone, and the plantation by clone interaction affected tree growth parameters significantly. Mean clone stem volume across sites from largest to smallest was: 49-177, OP-367, 50-197, 52-225, PC-6, 50-194, 58-280, 15-29, and Lombardy poplar. Attempts to correlate attack rating with any parameter of tree size were unsuccessful. Combining growth data and attack rating, OP-367 would be recommended for planting in arid regions east of the Cascade Mountains, followed by PC-6, 50-194 and 58-280. Future hybrid poplar breeding for this region should consider P. nigra as a parent. West. J. Appl. For. 18(4):276–280.
Foliar Nutrient Characteristics of Four Conifer Species in the Interior Northwest United States
Authors: Moore James A. , Mika Peter G. , Shaw Terry M. , Garrison-Johnston Mariann I.
Published: August 2019

This article provides foliar nutrient concentration distributions and sample size calculations for Douglas-fir, grand fir, ponderosa pine, and lodgepole pine. Managers can obtain foliar nutrient values from their own lands and use this information to make judgments on the relative nutrient status of forest stands. Foliage was collected from unfertilized trees at 160 different research sites of the Intermountain Forest Tree Nutrition Cooperative spanning a 16 yr period from 1982 to 1997. Douglas-fir showed the lowest variation in foliar nutrient concentrations, while grand fir was the most variable of the species sampled. Nitrogen was the least variable and Mn and Mo generally the most variable elements for all species. Grand fir had much higher foliar concentrations of K and Ca than the other species. Ponderosa pine had the highest foliar N concentrations. The pines generally have lower nutrient concentrations than the firs, with the exception of Zn. Western hemlock habitat types showed lower Douglas-fir foliar Ca, Mg, and B concentrations, but higher K concentrations than other habitat type series. Douglas-fir growing on soils derived from meta-sedimentary rocks generally had lower foliar nutrient concentrations than those growing on other rock types. West. J. Appl. For. 19(1):13–24.
Early Thinning in Mixed-Species Plantations of Douglas-Fir, Hemlock, and True Fir Affected by Armillaria Root Disease in Westcentral Oregon and Washington: 20 Year Results
Authors: Filip Gregory M. , Ganio Lisa M.
Published: August 2019

Four 10- to 20-yr-old plantations were treated to determine the effects of precommercial thinning on tree growth and mortality caused by Armillaria root disease in the Cascade Range of western Oregon and Washington. One plantation was Douglas-fir and noble fir, one Douglas-fir and western hemlock, one Douglas-fir alone, and one Shasta red fir and mountain hemlock. After 20 yr, differences in crop tree mortality between thinned and unthinned plots were not significant (P = 0.9768). Quadratic mean diameter growth of crop trees, however, was significantly (P = 0.0053) greater in thinned than in unthinned plots. Crop tree basal area/ac growth was significantly (P = 0.0008) greater in thinned plots. There were no significant (P = 0.6647) differences in basal area/ac growth of all trees between thinned and unthinned plots. Apparently, from a root-disease perspective, precommercial thinning does not affect incidence of crop-tree mortality after 20 yr, but individual and per acre tree growth of crop trees increase significantly. West. J. Appl. For. 19(1):25–33.
A Comparison of Rating Systems for Dwarf Mistletoe-Induced Witches' Brooms in Ponderosa Pine
Authors: Parker Thomas J. , Mathiasen Robert L.
Published: August 2019

We compared four methods of assessing dwarf mistletoe infection and estimating volume of dwarf mistletoe-induced witches' brooms in ponderosa pine (Pinus ponderosa). Witches' brooms can provide important wildlife habitat and can influence fire behavior. We used Hawksworth's dwarf mistletoe rating system (DMR), Tinnin's broom volume rating system (BVR), an estimate of the percentage of live crown occupied by witches' brooms (PCB), and a new system, total broom volume (TBV). We rated 12,536 trees for southwestern dwarf mistletoe (Arceuthobium vaginatum subsp. cryptopodum) infection and broom volume. Using Hawksworth's DMR and Tinnin's BVR systems, we were not able to distinguish trees with different witches' broom volumes at all sample sizes. At all sample sizes, TBV ratings accurately and precisely identified amount of witches' broom volume. We recommend that TBV be used to quantify witches' broom volume in ponderosa pine where wildlife habitat and fire ecology are primary concerns. West. J. Appl. For. 19(1):54–59.
A Case Study on the Economics of Thinning in the Wildland Urban Interface
Authors: Larson Debra S. , Mirth Richard
Published: August 2019

This is a case study, supplemented by an economic model, of one 85 ac ponderosa pine (Pinus ponderosa) dominated stand, called Unit 16, that was treated during the summer of 2001. Unit 16 is located in the Greater Flagstaff Forests Partnership's Fort Valley project area of the Coconino National Forest and is part of the Flagstaff, AZ wildland urban interface. The silvicultural prescription was a full restoration prescription anchored to the presettlement condition and was limited by a 16 in. dbh cutting cap. The operational strategy for the merchantable material was hand felling, limbing, topping, bucking in the forest, and forwarding of logs to the landing for loading on waiting trucks. The nonmerchantable trees were cut and rough piled, along with limbs and tops. The economic model estimated the logging contractor's costs to total $124,117. His total revenue stream during the summer of 2001 was detrimentally impacted by two unforeseen changes in his market. His normal purchaser of wood from small trees <8.0 in. dbh was unable to purchase this wood and his other market reduced its purchase price by 11%. As a result, his projected income went from providing a small profit of $7,857 to a loss of $3,284. Costs to the Forest Service to prepare the unit and to conduct postthinning activities were estimated to total $31,9160. Net costs to the Greater Flagstaff Forests Partnership in the form of a service contract with the logger totaled $17,000. West. J. Appl. For. 19(1):60–65.
Douglas-Fir Growth and Yield: Research 1909–1960
Authors: Curtis Robert O. , Marshall David D.
Published: August 2019

Systematic research on growth and yield of Douglas-fir began in 1909. This line of early research evolved over time and culminated in publication of USDA Bulletin 201, The Yield of Douglas-fir in the Pacific Northwest. B201 had an enormous influence on development of Douglas-fir forestry and was arguably the most influential single research publication ever produced in the Pacific Northwest. We review the evolution of this research and some associated topics, and the role of the major personalities involved. West. J. Appl. For. 19(1):66–68.
Integrating Knowledge for Simulating Vegetation Change at Landscape Scales
Authors: Chew Jimmie D. , Stalling Christine , Moeller Kirk
Published: August 2019

Managers of public lands are increasingly faced with making planning decisions for dynamic landscapes with conflicting objectives. A modeling system has been designed to serve as a decision support system to help managers and resource specialists integrate the available knowledge of vegetation change and disturbance processes, and quantify concepts that are often difficult to interpret for specific landscapes. The system is named SIMPPLLE, an acronym taken from “SIMulating vegetation Patterns and Processes at Landscape scaLEs.” SIMPPLLE can be used to help define and evaluate future conditions at landscape scales, to identify areas that are more prone to disturbances over a given time frame, to identify the options for influencing these disturbance processes, and to help design and evaluate different strategies for achieving desired future conditions. The emphasis in this article is to give an overview of the design of the system, the types of knowledge integrated, and the type of output produced. The initial validation work discussed indicates that the approach used for capturing and integrating process knowledge in SIMPPLLE does predict realistic results at landscape scales. SIMPPLLE provides managers a tool to integrate and interpret concepts of desired future conditions, range of variability, and the interaction between vegetation patterns and disturbance processes. SIMPPLLE provides a way to help evaluate proposed management scenarios within a future that includes stochastic processes. West. J. Appl. For. 19(2):102–108.
Sensitivity of a Riparian Large Woody Debris Recruitment Model to the Number of Contributing Banks and Tree Fall Pattern
Authors: Bragg Don C. , Kershner Jeffrey L.
Published: August 2019

Riparian large woody debris (LWD) recruitment simulations have traditionally applied a random angle of tree fall from two well-forested stream banks. We used a riparian LWD recruitment model (CWD, version 1.4) to test the validity of these assumptions. Both the number of contributing forest banks and predominant tree fall direction significantly influenced simulated riparian LWD delivery, but there was no apparent interaction between these factors. Pooled across all treatments, the average predicted 300-year cumulative LWD recruitment was 77.1 m3/100 m reach with both banks forested compared to 49.3 m3/100 m reach when only one side was timbered. Total recruitment within bank cover categories (one versus both forested) depended on the directionality of the falling stem. When only one bank was forested, the CWD model predicted the same riparian LWD recruitment for the random and CWD default tree fall patterns (∼39 m3/100 m reach), the pattern biased toward the channel yielded twice this volume, a pattern quartering toward the channel produced 64% more LWD, and the pattern paralleling the channel contributed almost 30% less than random. With both banks forested, the random, default, and quartering simulations resulted in similar delivery (about 78 m3/100 m reach), the pattern biased toward the channel contributed almost 14% more LWD, and the parallel pattern yielded 26% less. Because CWD is similar in design and operation to other riparian LWD recruitment models, it follows that any simulation of wood delivery to streams should be checked for their consistency with local forest cover and tree failure patterns. West. J. Appl. For. 19(2):117–122.
Arboreal Squirrel Response to Silvicultural Treatments for Dwarf Mistletoe Control in Northeastern Oregon
Authors: Bull Evelyn L. , Heater Thad W. , Youngblood Andrew
Published: August 2019

Various silvicultural treatments are commonly used to sanitize stands by removing trees infected with dwarf mistletoe (Arceuthobium spp.), yet witches' brooms in trees infected with dwarf mistletoe often provide structures used by many wildlife species. We compared relative abundance, habitat use, and area of use of red squirrels (Tamiasciurus hudsonicus) and northern flying squirrels (Glaucomys sabrinus) before and after two different treatments designed to remove a range of dwarf mistletoe-caused witches' brooms in northeastern Oregon in 1998–2002. Dwarf mistletoe sanitation treatments included: (1) an island treatment, with retention of up to 0.5 ha groups of trees containing witches' brooms in evenly distributed uncut islands, and all harvest activity confined to thinning from below outside these islands to eliminate trees containing witches' brooms; and (2) a total removal treatment, which consisted of removing all trees that contained a witches' broom estimated to be >25 cm in diameter. Before treatment, over half of the red squirrels and northern flying squirrels in the treatment area occupied summer rest sites in witches' brooms on large Douglas-fir (Pseudotsuga menziesii). Live trapping indicated a pretreatment abundance of 1.0 per 100 trap/nights for red squirrels and 0.4 per 100 trap/nights for northern flying squirrels, and a posttreatment abundance of 2.1 per 100 trap/nights for red squirrels and 0.2 per 100 trap/nights for northern flying squirrels. Type of rest site and amount of red squirrel reuse did not change after the island treatment, although the number of red squirrels located in rest sites increased with the island treatment. Most of the red squirrel locations occurred within the islands. Area of use by red squirrels did not change with island treatment. Type of rest site used by red squirrels and northern flying squirrels shifted after the total removal treatment from mostly witches' brooms to predominantly tree cavities. Area of use by red squirrels increased from 1.8 to 7.6 ha after the total removal treatment. Results suggest that retention of trees containing witches' brooms in small groups or islands offers an opportunity to retain rest site habitat, although northern flying abundance declined with both treatments. West. J. Appl. For. 19(2): 133–141.
Early Career Development of Foresters, Range Conservationists, and Wildlife/Fisheries Biologists in Two Western Forest Service Regions
Authors: Kennedy James J.
Published: August 2019

This paper examines how newly hired foresters are adapting to their profession and a career in the Forest Service in comparison to their range conservationist and wildlife/fisheries biologist colleagues. The sample consisted of 44 foresters, 27 range conservationists, and 38 biologists with 1-3 years permanent Forest Service employment in the Intermountain and Pacific Northwest regions, as well as 35 of their immediate supervisors. About half the sample were women. Most young recruits have found satisfying careers both in their profession and within the Forest Service. Foresters and range conservationists seemed to more readily accept organizational values and develop a long-term commitment to the Forest Service than did their biologist colleagues. Some women had difficulty adapting to their professions and to the Forest Service. The professional and sexual diversity of these new types of recruits has implications for their integration into the Forest Service, acceptance of their values and loyalties, and the evolution of a natural resources agency traditionally dominated by male foresters. West. J. Appl. For. 2:10-14, January 1987
Elk Hiding and Thermal Cover Guidelines in the Context of Lodgepole Pine Stand Density
Authors: Smith Frederick W. , Long James N.
Published: August 2019

We present a technique to evaluate how ungulate hiding and thermal cover guidelines affect density management of lodgepole pine (Pinus contorta) stands. Modification of a lodgepole pine density management diagram results in a graphical tool useful to forest managers interested in wildlife habitat evaluation. This technique can be used to determine the amounts of cover provided by silvicultural prescriptions and to evaluate cover status of existing stands. Stand structures that meet the guidelines were determined by simulation modeling and field sampling. Current hiding cover requirements were met when summed dbh was above about 5,000 in./ac or when summed crown diameters were greater than 630 ft/ac. The thermal cover requirement was determined to be the most restrictive element of the guidelines. West. J. Appl. For. 2:6-10, January 1987.
Simulating Succession of Riparian Spruce Forests and White-Tailed Deer Carrying Capacity in Northwestern Montana
Authors: Jenkins Kurt J. , Wright R. Gerald
Published: August 2019

Rates of succession were determined during the period 1945-80 in six floodplain plant communities along the North Fork of the Flathead River, Montana. A succession model was developed to forecast the long-range effects of land-use change on the carrying capacity of white-tailed deer winter range. The areas occupied by mature spruce (Picea englemannii x glauca hybrid) and spruce-black cottonwood (Populus trichocarpa) forests on the floodplain were relatively constant between 1945-1980. Early seral types were more variable due to short-term variations in river flow. Successional modelling demonstrated the effects of two timber harvesting strategies on white-tailed deer populations. Simulated populations declined following two timber harvesting schedules, but recovered after cessation of harvest. An additional application of the model showed the potential effects of increased erosion rates on deer populations and demonstrated the versatility of land succession models for resource monitoring. West. J. Appl. For. 2(3):80-83, July 1987
Old-Growth Douglas-Fir and Western Hemlock: A 36-Year Record of Growth and Mortality
Authors: DeBell Dean S. , Franklin Jerry F.
Published: August 2019

Growth and mortality were measured at 6-year intervals in a 1,180-acre old-growth stand in southwestern Washington. Principal tree species were Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla), Pacific silver fir (Abies amabilis), western redcedar (Thuja plicata), and western white pine (Pinus monticola). They composed 59, 27, 6, 6, and 1%, respectively, of the total cubic volume (13,290 ft³) in 1947. Gross volume growth averaged 94 ft³ per acre per year, and mortality averaged 86 ft³ per acre per year. Net growth was therefore minimal, and total stand volume remained nearly constant for 36 years. Douglas-fir, which accounted for only one-third of the gross growth and nearly one-half of the mortality, is losing dominance to western hemlock, which provided nearly one-half the gross growth and only 28% of the mortality. Pacific silver fir increased in importance in the lower canopy and composed 60% of the in-growth. Thus, although net gain in timber volume was nil, substantial changes occurred in stand characteristics during the 1947-1983 period. West. J. Appl. For. 2(4):111-114, October 1987.
Correlations Between Overtopping Vegetation and Development of Douglas-Fir Saplings in the Oregon Coast Range
Authors: Chan Samuel S. , Walstad John D.
Published: August 2019

The response of Douglas-fir (Pseudotsuga menziesii) saplings to overtopping vegetation on three northeast-facing sites in the Oregon Coast Range was studied for two years. As amount of overtopping brush increased, sapling growth (as indicated by size) generally decreased. Basal stem diameter growth was most reduced, but similar reductions in growth occurred for tree height and other morphological features. West. J. Appl. For. 2(4):117-119, October 1987.
Growth and Foliar Nutrition of Douglas-Fir Seedlings Provided with Supplemental Polymer-Coated Fertilizer
Authors: Jacobs Douglass F. , Haase Diane L. , Rose Robin
Published: August 2019

Polymer-coated fertilizer (PCF) provides a potential means to optimize nutrient delivery for plant uptake, while minimizing leaching. Coating technology varies by manufacturer, which may alter patterns of nutrient release over time among comparable products. Three months following sowing, Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings were transplanted into containers with Osmocote Plus (OS) (15-9-12) and Apex (AP) (16-5-9) PCF (each with 5–6 month longevity) applied at four rates (0, 600, 1200, and 1800 mg total N per seedling) as a supplement to periodic addition of conventional water-soluble fertilizer. Seedlings fertilized with OS had 11% greater stem diameter growth during the first 4 months after transplant than those fertilized with AP, but differences were negligible after 9 months. After 4 months, foliar concentrations were 11% higher for N and 10% higher for P in seedlings fertilized with AP, although contents were the same. These results suggest that different PCF types have variable temporal patterns of nutrient release, which may affect seedling development over time. Differences among products must be understood by growers to help formulate fertilizer prescriptions that optimize plant response. Seedling response varied marginally among PCF rates, suggesting little benefit to PCF when used in conjunction with water-soluble fertilizer. West. J. Appl. For. 20(1):58–63.
Top Height Estimation in Lodgepole Pine Sample Plots
Authors: García Oscar , Batho Adrian
Published: August 2019

Top height definitions are often based on the heights of a certain number of the largest trees per unit area, such as the largest 100/ha. Recognizing that results vary with the extent of the reference area, this area is specified in the British Columbia definition, basing top height on the largest tree in a 0.01-ha plot. The problem is how to estimate top height when data is available for larger plots, without the information needed to subdivide them into 0.01-ha subplots. The usual largest 100/ha overestimates the correct value, and we find that the bias can be substantial. We evaluate two alternatives for natural lodgepole pine stands, using data from 0.04- and 0.08-ha sample plots. The improved estimators considerably reduce bias, although some bias due to spatial size autocorrelations remains. Autocorrelation was found to be predominantly positive, and some implications for growth and yield prediction are mentioned. West. J. Appl. For. 20(1):64–68.
Efficiencies of Traditional and Digital Measurement Technologies for Forest Operations
Authors: Kiser Jim , Solmie Derek , Kellogg Loren , Wing Michael G.
Published: August 2019

Higher-precision technologies may increase measurement accuracy and efficiency for operational layout while decreasing total planning costs. Although a number of trials have been completed on the potential implementation of some of these new technologies, few have quantified the benefits of such devices in an operational setting. Unit boundaries for 16 (∼1 ac) units were measured by three surveying techniques, comprising (1) a string box, manual compass, and clinometer; (2) a laser, digital compass, and digital data collector; and (3) a GPS. Collected data were compared to a fourth benchmark method established with a total station. Techniques were statistically analyzed and error distributions were developed at either a unit or an individual data-point scale. Time and cost studies were conducted to determine the overall efficiencies of each technique. Our results should assist forest resource managers in their decisions when selecting alternate measurement tools for collecting spatial data. West. J. Appl. For. 20(2):138–143.
Comparative Susceptibility of Conifers to Western Hemlock Dwarf Mistletoe in the Cascade Mountains of Washington and Oregon
Authors: Mathiasen Robert L. , Daugherty Carolyn M.
Published: August 2019

A total of 24 mixed conifer stands in Washington and Oregon infested with western hemlock dwarf mistletoe (Arceuthobium tsugense subsp. tsugense) were sampled to compare host susceptibility to this parasitic plant. Temporary circular plots were established around dominant, severely infected western hemlocks (Tsuga heterophylla). Within plots, species, diameter at breast height, and dwarf mistletoe rating (6-class system) were determined for each live tree. More than 5,700 trees were sampled in 275 plots. Based on the incidence of infection, tree species were assigned to host susceptibility classes. Western hemlock is classified as the only principal host of western hemlock dwarf mistletoe. Pacific silver fir (Abies amabilis), noble fir (Abies procera), and mountain hemlock (Tsuga mertensiana) are classified as occasional hosts. Resource managers can use the host susceptibility classifications based on this study for decisions regarding which trees to retain when selectively harvesting mixed conifer stands infested with western hemlock dwarf mistletoe in the Pacific Northwest. West. J. Appl. For. 20(2):94–100.
Credit Availability: A Possible Barrier to Growth for the Alaska Forest Products Industry?
Authors: Donovan Geoffrey , Hesseln Hayley , Garth John
Published: August 2019

Historically, the Alaska forest products industry has been driven by pulp production and the export of logs and cants primarily to Japan. Economic stagnation in Japan, the closure of Alaska's two pulp mills, harvest restrictions, and increased competition have severely impacted the industry. To survive, the industry must make significant investments in capital equipment, which requires adequate access to business credit. This article examines whether credit availability is a barrier to the future growth of the industry. Data were collected through a mail survey in spring 2002. Our results show that credit rationing is prevalent throughout the industry. Lack of experience and low collateral are identified as the two main causes. An educational program and loan guarantees are offered as policy prescriptions to help alleviate credit rationing. West. J. Appl. For. 20(3):177–183.
Ten-Year Growth and Epicormic Sprouting Response of Western Larch to Pruning in Western Montana
Authors: Waring Kristen M. , O'Hara Kevin L.
Published: August 2019

Western larch (Larix occidentalis Nutt.) is a fast-growing, deciduous conifer that is often managed for timber production in the inland Northwest. No previous study has documented the response of this species to artificial pruning. Trees pruned as part of a pruning cost study in 1992 were followed for 10 years to assess growth and epicormic sprout response. Trees were pruned to two heights: 2.4 and 5.5 m in three stands in western Montana. Epicormic sprouting occurred in a majority of trees in the first 2 years after pruning, but subsequently many sprouts died so that by year 10, only approximately 30% of trees had sprouts. Volume increment was adversely affected by more severe pruning among smaller trees pruned to the shorter lift. The volume increment of the trees that received the 5.5 m lift was generally unaffected, but trees receiving the 2.4 m lift were more sensitive to pruning. Initial tree diameter and residual crown length were important variables in predicting the 10-year volume increment in pruned trees. West. J. Appl. For. 20(4):228–232.
Harvesting Impacts on Understory Regeneration in Two-Storied Douglas-Fir Stands
Authors: Newton Michael , Cole Elizabeth C.
Published: August 2019

Conifers were underplanted beneath thinned 50-year-old Douglas-fir stands in western Oregon. Overstories had been thinned to four densities ranging from 18 to 31 m2/ha (78–134 ft2/ac) from stands originally stocked at about 23 to 51 m2/ha (100–220 ft2/ac). Seedlings beneath some densities showed declining vigor in the first 8 years after planting, resulting from overstory growth of about 5.7 m2/ha (25 ft2/ac) in that period. Some of the stands were rethinned to remove the basal area accrued since the first thinning. Timber was harvested by ground and cable equipment, with log length averaging over 10 m (32 ft) and averaging 52 m3/ha (4.7 mbf/ac, Scribner rule) on 29 ha (72 ac). Overall, 40% of planted seedlings were damaged by logging. Among the four species planted, between 18% and 30% of seedlings alive at the time of harvest were removed or lodged/buried under debris. An additional 13% to 16% had broken or dead tops or were bent at a lean greater than 45 degrees. Two years after thinning, damaged seedlings grew an average of 10 cm less than those not damaged. Unless densities are initially very low at the time of planting, e.g., <18 m2/ha (78 ft2/ac), rapidly growing overstories are likely to suppress understory plantings. Thinning will inflict losses unless logging is carefully laid out and executed, and long log lengths are minimized.
Evaluation of Two Pheromone Baits for Containment and Concentration of Attack by the Western Balsam Bark Beetle, Dryocoetes confusus (Coleoptera: Curculionidae)
Authors: Jeans-Williams Nicole L. , Borden John H.
Published: August 2019

In past studies, the greatest response by the western balsam bark beetle Dryocoetes confusus Swaine (Coleoptera: Scolytidae) to traps and baited trees was obtained with blend of (+)-exo- and (±)-endo-brevicomin, which mimic the natural male-produced aggregation pheromone. We conducted a tree-baiting experiment to determine whether low-release enantiospecific blends [9:1 (+) exo-brevicomin:(+)-endo-brevicomin, or 9:2 (+)-exo-brevicomin: (±)-endo-brevicomin released at 0.3, 0.1, or 0.03 mg/day] could compete with or improve the efficacy of the standard (±)-exo-brevicomin bait released at 1.2 mg/day. In this experiment, the standard and experimental baits were almost 90% effective in inducing attack by D. confusus. Two subsequent 9-ha block experiments compared the ability of the standard and 9:2 (+)-exo-brevicomin:(±)-endo-brevicomin baits to contain and concentrate infestations before harvesting. Again, both baits were equally effective as potential stand management tools based on almost 100% attack on baited trees, green-to-red tree ratios between 3:1 and 5:1, and redistribution of the majority of attack around baited rather than red trees from which beetles could emerge. We recommend that the standard bait continue to be offered commercially for treatment of stands infested by D. confusus.
Improvements in Value Recovery through Low Stump Heights: Mechanized versus Manual Felling
Authors: Hall Ryan , Han Han-Sup
Published: August 2019

Stump heights were measured on two blocks harvested during the summer of 2000 in north-central British Columbia. Each block was of similar stand and terrain characteristics, consisting mainly of subalpine fir (Abies lasiocarpa) with minor components of white spruce (Picea glauca × P. engelmannii) on gentle slopes. The blocks were harvested by two different contractors using different felling methods: mechanized felling with a feller-buncher and manual felling with a chainsaw. The average measured stump height from mechanized felling was 8.8 cm lower than that of manual felling, measuring 21.9 and 13.1 cm, respectively. When the saw kerf of felling equipment and stump-pull were included, the average stump height of mechanized felling was shown to be 5.8 cm (17%) lower than manual felling. High-end and low-end potential value losses were determined based on average sawlog values (Canadian [CN] $60/m 3 ) and pulp log values (CN$40/m 3 ), respectively. The potential value loss from manual felling was estimated to be up to CN$0.33/tree more than from mechanized felling. This result indicated that mechanized felling recovered up to CN$160/ha over manual felling when an average sawlog value and the stand density information from the study site were used in the calculation. The study demonstrated that lower stump heights than the 30 cm maximum stump height set by the Forest Practices Code of British Columbia are attainable with both felling methods. Sensitivity analysis was performed to determine the potential value and volume gains for a range of stump heights from 0 to 30 cm. Operational constraints were identified in the study, and recommendations for minimizing stump heights are presented.
Predicting Spruce Weevil Damage in Sitka Spruce in the Northern Oregon Coast Range
Authors: Lysak Teresa , Ross Darrell W. , Maguire Douglas A. , Overhulser David L.
Published: August 2019

The spruce weevil, Pissodes strobi (Peck), is a serious pest of Sitka spruce, Picea sitchensis (Bong.) Carr, in Oregon. Weevils cause damage by killing the leader of a tree, resulting in defects such as crooks and forks that can reduce tree merchantability. In this study,Sitka spruce stands 16–25 years old were surveyed to explore relationships among stand and site characteristics and weevil damage. Trees had an average of 2.8 defects, ranging from 0 to 10, with minor crooks being the most common type of defect. All stands had damage in at least 58% of the trees. The amount of damage was found positively correlated with distance from the ocean and growth rate and negatively correlated with elevation, latitude, and spruce density. These variables together accounted for 61% of variation in the amount of damage.
Incidence of Heterobasidion annosum in Mixed-Conifer Natural Regeneration Surrounding Large True Fir Stumps 20–25 Years after Harvesting in Northeastern Oregon
Authors: Filip Gregory M. , Schmitt Craig L. , Chadwick Kristen L.
Published: August 2019

High-elevation true fir stands on federal lands have a long history of selective harvesting. In 1989 a high frequency (89%) of Heterobasidion annosum, the cause of annosus root disease, was found in residual true fir stumps (mean, 20-in. diameter) cut 5–9 years earlier in northeast Oregon. In 2004, H. annosum was found at the stump surface of 29% of the natural conifer regeneration (mean, 18 years) within 20 ft of infected residual stumps. A total of 16 of 122 (13%) live saplings had H. annosum–caused stain or decay. Only 3% of 126 sample trees, however, were dead and infected by H. annosum. Infection was confirmed in 62% of decayed trees, 33% of stained trees, and 22% of trees with no visible stain or decay at the stump surface. Only 3 of 122 living saplings showed typical root disease crown symptoms (chlorosis), but only one of these had H. annosum. Only 1 of 16 live saplings with H. annosum–caused stain or decay was chlorotic. Incidence of infection was 44% in Engelmann spruce (7 of 16 trees), 31% in Douglas-fir (5 of 16 trees), 31% in subalpine fir (4 of 13 trees), and 27% in grand fir (21 of 77 trees). The S-type of H. annosum was confirmed in a sampled grand fir. There were no significant differences between H. annosum–infected and apparently healthy trees regarding live crown ratio and distance from infected residual stumps. Infected trees, however, were significantly (P = 0.025) larger in diameter than apparently healthy trees. The dynamics of H. annosum infection in spruce and Douglas-fir in northeast Oregon are discussed as well as treating true fir stumps with boron-containing products to prevent stump infection by H. annosum. West. J. Appl. For. 21(4):178–184.