bluuebunny/crossref_metadata_2025_split huggingface dataset:
Canada–U.S. Softwood Lumber Trade Revisited: Substitution Bias in the Context of a Spatial Price Equilibrium Framework
Authors: Mogus Anthony , Stennes Brad , van Kooten G. Cornelis 
Published: April 2024

Abstract
Softwood lumber trade between Canada and the United States has been characterized by various trade restrictions. Many studies have attempted to quantify the effects of such sanctions, modeling softwood lumber as a single, homogenous commodity, although recent research suggests that this may be a misleading assumption because softwood lumber products vary. In this article, we address the problem of “substitution bias” in estimates of the effects of trade restricting policies. A spatial price equilibrium model is used to examine the effects of import duties on Canadian lumber, comparing these with the effects of an export tax and quota. By controlling for substitution bias, our estimates indicate that a larger share of the tariff burden is placed on U.S. consumers, with Canadian producers suffering less injury compared to estimates based on the traditional assumption of a homogenous product. In addition, by comparing the net impact associated with the alternative policy regimes, a policy equivalence is found. Results suggest that the short-run impact of a trade restriction is largely independent of the policy regime incorporated, with the collection of quota rents or tax revenues determining overall winners and losers.
Modeling Postfire Mortality of Ponderosa Pine following a Mixed-Severity Wildfire in the Black Hills: The Role of Tree Morphology and Direct Fire Effects
Authors: Keyser Tara L. , Smith Frederick W. , Lentile Leigh B. , Shepperd Wayne D. 
Published: April 2024

Abstract
We examined the relationship among tree size, crown and stem damage, and 5 years of postfire mortality of ponderosa pine (Pinus ponderosa Dougl. ex. P. & C. Laws.) in the Black Hills following a large, mixed-severity wildfire. We measured tree morphology and direct fire effects on 963 trees and assessed individual tree mortality annually from 2001 to 2005. We used logistic regression to model tree mortality as a function of tree morphology (dbh) and bark thickness (BARK) and direct fire effects [percentage of the live crown scorched (PSCOR) and basal char measured as the percentage of the bole charred below 30 cm (CHAR)]. Models using dbh and BARK were modeled separately due to correlation between the variables. In all models, mortality decreased with increasing dbh and BARK and increased with increasing PSCOR and CHAR. Basal char contributed to the mortality of trees less than 40 cm but became less influential as dbh and BARK increased. Overall, probability of mortality modeled as a function of dbh, PSCOR, and CHAR correctly predicted the status of 78% of trees, whereas the model predicting mortality as a function of BARK, PSCOR, and CHAR had an increase in prediction accuracy of only 1%.
Capital Structure in the United States Forest Products Industry: The Influence of Debt and Taxes
Authors: Mendell Brooks C. , Sydor Tymur , Mishra Neena 
Published: April 2024

Abstract
This article investigates financing practices across firms in the forest products industry by studying the relationship between debt and taxes hypothesized in finance theory. In testing the theoretical relationship between taxes and capital structure for 20 publicly traded forest industry firms for the years 1994–2003, we find a negative relationship between profitability and debt, a positive relationship between nondebt tax shields and debt, and a negative relationship between firm size and debt. All three results run counter to theoretical expectations. Results indicate that, controlling for size, firms in the forest products industry with higher market valuations and pretax earnings used more conservative financing strategies. Also, the article develops a dynamic panel model with fixed effects for each firm and residualization to address issues of multicollinearity.
Comparison of Distance-Dependent and Distance-Independent Stand Growth Models—Is Perfect Aggregation Possible?
Authors: Kokkila Tero , Mäkelä Annikki , Franc Alain 
Published: April 2024

Abstract
Selecting a suitable level of accuracy in stand growth estimations is a question of practical importance. A detailed model is more complicated and demands more initial information from the user to produce reliable results. Despite being correct and more precise, it may well be that the more detailed results give no practical bonus value. The essential part of the estimations could also have been received with coarser means. We have used three levels of stand description accuracy. The first is a mean tree model (MTM), where all trees are assumed identical. The second is a distribution-based model (DBM), where size differences are allowed. Both versions are distance-independent and the spatial configuration of the stand is considered random. The third is a spatially explicit model (SEM), where all trees are described individually and their spatial locations are taken into account. The core dynamics in all models are kept the same, so a previous model is a straightforward aggregation of the latter one. The possibility of a perfect aggregation was examined both theoretically and by practical simulations. A process-based stand growth model ACROBAS was used to simulate the different levels of aggregation. The results demonstrate that under the Poisson assumption of stand spatial configuration there are hardly any differences among model aggregations. As mortality is not totally random in the SEM, the Poisson assumption does not hold through the whole simulation period. As the spatial configuration eventually tends toward regularity, the total growth in the stand is somewhat increased, which is evident in variables such as total stem volume and foliage mass. However, mean height and stocking density developments are almost identical in all models. This suggests that the mean height is “an almost perfect𠇍 aggregation variable.
Effect of Edge Trees on Harvester Positioning in Thinning
Authors: Ovaskainen Heikki , Uusitalo Jori , Sassi Tuomo 
Published: April 2024

Abstract
The objective of this study was to discover the influence of edge trees, the trees along the side of the strip road, on the positioning of modern single-grip harvester during the first commercial thinning. The results indicate that there is one main working location in the strip road where the harvester is positioned in a distance of two consecutive edge trees. This main location is determined by an edge tree located about 1.2 m behind the boom base. There are also other working locations within a certain distance but in most cases the harvester was positioned same way to the main location, which enables the least restricted boom operations in the boom working sector. Positioning the harvester according to the edge trees does not explain the considerable productivity differences among experienced harvester operators, but the awareness and significance of the edge trees give trainees a valuable basis for outlining and planning work in early stages of training. The present findings are also beneficial from the cutting damage and harvester configuration points of view.
Determinants of Forest Land Prices in Northern Minnesota: A Hedonic Pricing Approach
Authors: Snyder Stephanie A. , Kilgore Michael A. , Hudson Rachel , Donnay Jacob 
Published: April 2024

Abstract
A hedonic price model was developed to analyze the market for undeveloped forestland in northern Minnesota. The data included 387 forestland parcels purchased in 2001 or 2002. Information describing parcel physical characteristics, amenity features, merchantable timber volume, development trends, terms of financing, and several proximity, distance, and adjacency conditions were tested for their influence on forestland prices. The model's independent variables collectively explained approximately 50% of the variation in per hectare sale price. The method by which forestland sales were financed, road access and density, proximity to population centers, and presence of lake or river frontage had the largest positive influences on per hectare sale prices. Adjacency to public land had an unexpectedly large, negative influence on sale price. Importantly, a parcel's merchantable timber volume was not found to be a significant predictor of forestland sale price. In general, forestland markets were driven by three major influences: land development pressures, presence of or close proximity to a water body, and the use of contract for deed financing.
Compatible Estimators of the Components of Change for a Rotating Panel Forest Inventory Design
Authors: Roesch Francis A. 
Published: April 2024

Abstract
This article presents two approaches for estimating the components of forest change utilizing data from a rotating panel sample design. One approach uses a variant of the exponentially weighted moving average estimator and the other approach uses mixed estimation. Three general transition models were each combined with a single compatibility model for the mixed estimation approach. The four resulting estimation systems are compared and contrasted in a sample simulation study covering four simulated populations.
Effects of Timber Harvest on Suspended Sediment Loads in Mica Creek, Idaho
Authors: Karwan Diana L. , Gravelle John A. , Hubbart Jason A. 
Published: April 2024

Abstract
Long-standing concerns exist regarding timber harvest and subsequent sediment impacts on aquatic resources. Intensive studies on contemporary harvest practices remain rare, particularly in the interior Pacific Northwest. To investigate this, a network of seven automated stream monitoring flumes was installed in the Mica Creek Experimental Watershed, in northern Idaho. Beginning in 1991, water samples collected at each flume under both flow-based and stream-stage storm rise conditions have been analyzed for total suspended solids (TSS). This period of record encompasses a pretreatment time interval from 1991 to 1997, and two treatment time intervals: post-road from 1998 to 2001 and post-road/post-harvest from 2001 through 2004. Treated and control catchments were statistically compared using a paired watershed approach for immediate and recovery time intervals corresponding to each treatment activity, road construction and timber harvest. The impacts corresponding to road construction remain difficult to discern. The impacts corresponding to timber harvest differ based on harvest treatment and time period of analysis. Results suggest a correlation between increased sediment loads and clearcutting for a brief period following the harvest. No significant correlation was found in the partial cut watershed. Continued monitoring at these sites is planned to evaluate trends over subsequent years.
Headwater Riparian Microclimate Patterns under Alternative Forest Management Treatments
Authors: Rykken Jessica J. , Chan Samuel S. , Moldenke Andrew R. 
Published: April 2024

Abstract
Management of headwater streams and their riparian zones has included the implementation of forested riparian buffers, which are intended to protect ecological processes (such as microclimate) and biota, but the appropriate widths for these buffers have been widely debated. We measured the magnitude and extent of microclimatic gradients associated with headwater streams in mature unmanaged forests, and determined whether these patterns were maintained in clearcut harvested units with and without a 30 m-wide riparian buffer on each side of the stream. We measured air temperature, soil temperature, and relative humidity between 1 and 70 m from the stream in five replicate blocks of three treatments each in western Oregon. Results indicated the strongest stream effect on air temperature and relative humidity to be within 10 m of the stream in all management treatments at 3:00 pm, and gradients were evident to 20 m in the forested treatment. The clearcut was significantly hotter (air and soil) and drier than either the riparian buffer or the forest treatments at 3:00 pm. The riparian buffer and forest had similar microclimates at all distances from the stream, suggesting that the 30-m buffer adequately protected the riparian microclimatic gradient. We hypothesize that the strong stream effect on microclimate in the riparian zone serves a critical role in mitigating the influence of microclimatic “edge effects” associated with the forest-clearcut edge. Biota dependent on cool, humid microclimates provided by riparian zones will benefit from the implementation of riparian buffers in harvest units.
Effects of Clearcutting and Riparian Buffers on the Yield of Adult Aquatic Macroinvertebrates from Headwater Streams
Authors: Moldenke Andrew R. , Ver Linden Carolyn 
Published: April 2024

Abstract
We studied the emergence of Ephemeroptera, Plecoptera and Trichoptera (EPT) from headwater streams in Pacific Northwest conifer forests with emergence traps. We analyzed the effects of silvicultural management (clearcutting and riparian buffering) on insect species assemblages as a measure of the quantity of food resource available to insectivorous predators. Canopy removal increased the biomass and density of total EPTs and all feeding guilds except scrapers. Buffering does not change EPT yield from that of the mature forest (perhaps it decreases it), but the EPT community composition within the buffers becomes similar to that of adjacent clearcuts. Differences in community composition attributed to changes in elevation were more substantial than differences caused by silvicultural management. Forty percent of the species collected were restricted to one or another of the five sites.
Preliminary Study of the Effects of Headwater Riparian Reserves with Upslope Thinning on Stream Habitats and Amphibians in Western Oregon
Authors: Olson Deanna H. , Rugger Cynthia 
Published: April 2024

Abstract
We conducted a preliminary examination of the responses of stream amphibians and instream habitat conditions to alternative riparian buffer zones with forest thinning upslope. Pre and posttreatment surveys were carried out on 68 headwater stream reaches (including 23 unthinned reference reaches) at 11 sites in western Oregon. Streams were in managed conifer stands, 40 to 80 years old, where the thinning treatment reduced stands from 600 trees per hectare (tph) to 200 tph. Treatments consisted of four widths of riparian buffers approximately 6, 15, 70, and 145 m on each side of streams. Over three study years, 3,131 individuals of 13 species were detected. For the more common instream and bank species analyzed, capture rates persisted posttreatment with no negative treatment effect from thinning with any of the buffer widths. More animals were detected after thinning in treatment reaches compared to reference reaches for rough-skinned newts (Taricha granulosa Skilton) occurring on stream banks, and for instream coastal giant salamanders (Dicamptodon tenebrosus Baird and Girard). Treatment effects on instream habitat parameters were not detected. Interannual variation was evident for western red-backed salamanders (Plethodon vehiculum Cooper), and several habitat conditions including pool-riffle ratio, stream spatial intermittency, stream width, and down wood. Overall, riparian buffers with moderate upslope thinning (200 tph) seemed to have retained the aquatic vertebrate community along channels among sites in the first 2 years posttreatment; however, several limitations of the study reduce the inference of the findings, and these preliminary results are best interpreted as hypotheses for further investigation.
The Components of Change for an Annual Forest Inventory Design
Authors: Roesch Francis A. 
Published: April 2024

Abstract
The sample design of the USDA Forest Service's Forest Inventory and Analysis Program (FIA) with respect to a three-dimensional population (forest area × time) of tree attributes is formally defined and evaluated. The definitions for both the traditional components of growth, as presented by Meyer (1953, Forest Mensuration), and a discrete analog to the time invariant redefinition of the components of change given by Eriksson (1995, Forest Sci. 41(4):796–822), are compared and contrasted. Special problems in the application of the traditional definitions due to the continuous and overlapping temporal intervals featured in the sample design are explored. This exploration supports a contention that the traditional definitions are at a theoretical disadvantage because they are not based purely on the population(s) of interest, while the redefinitions dubbed the components of change by Eriksson (1995) were based solely on population attributes. The temporally discrete analog to the Eriksson definitions are used in this article to define the three-dimensional populations in terms of a set of mutually exclusive component matrices that can be summed to represent the entire population, independently of the sample design.
Interactive Effects of Soil Temperature and [CO2] on Morphological and Biomass Traits in Seedlings of Four Boreal Tree Species
Authors: Zhang Shouren , Dang Qing-Lai 
Published: April 2024

Abstract
To better understand how soil temperature will influence the responses of boreal trees to increasing atmospheric [CO2], one-year-old jack pine (Pinus banksiana lamb.), black spruce (Picea mariana [Mill.] B.S.P.), white spruce (Picea glauca [Moench] Voss), and current-year white birch (Betula paperifera Mash) seedlings were subjected to two [CO2] (360 versus 720 μmol mol−1) and three soil temperatures (T soil = 7, 17, and 27°C initially, increased to 10, 20, and 30°C 3 months later) for 4 months. The low T soil significantly suppressed height growth, stem biomass, and total biomass in white birch, black and white spruce, root collar diameter (RCD), and foliage biomass in white birch and white spruce, as well as root biomass in white birch under both ambient and elevated [CO2] and in white spruce under ambient [CO2]. This low T soil effect was much more significant in white birch than in the conifers. The [CO2] elevation significantly increased RCD, foliar biomass, and total biomass of the four species at all soil temperatures, stem biomass of all the species at the low T soil, and the root biomass of white birch at intermediate T soil. The data suggest that the [CO2] elevation compensated for the negative effects of low T soil, e.g., the low T soil significantly decreased the height and total biomass of black and white spruce at ambient [CO2], but not at elevated [CO2]. The high T soil had much smaller negative effects on growth and biomass than did the low T soil. Jack pine was the least responsive to T soil and [CO2]. In general, the ratios of stem, foliage, and root mass to total mass were much less responsive to the treatments than total or component biomass. Neither treatment significantly affected the volume/mass ratio of the stem in any of the four species. The data suggest that white birch and white spruce will benefit the most and jack pine will benefit the least from the increasing atmospheric [CO2].
Mountain Pine Beetle-Induced Changes to Selected Lodgepole Pine Fuel Complexes within the Intermountain Region
Authors: Page Wesley Green , Jenkins Michael James 
Published: April 2024

Abstract
The mountain pine beetle (Dendroctonus ponderosae Hopkins) is a forest insect that infests lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) forests in the Intermountain West. The often widespread mortality caused by the mountain pine beetle has been suggested to result in significant changes to stand structure, composition, and total fuel loading; however, little quantitative information that documents these changes is available. We examined mountain pine beetle–induced changes to ground, surface, and aerial fuels in lodgepole pine stands during current epidemics and 20 years after an epidemic. Results indicated that there were statistically significant increases in the amounts of fine surface fuels in recently infested stands, i.e., those stands ≤5 years past peak mortality. In the previously infested stands, there were large increases in the amounts of dead woody fuels in all but the smallest size classes, with a 7.8-fold increase in down woody fuels ≥7.62 cm in diameter. Live shrubs and the amount of subalpine fir (Abies lasiocarpa Nutt.) regeneration were also significantly greater in the postepidemic stands. The net result of epidemic mountain pine beetle activity was a substantial change in species composition and a highly altered fuels complex in which large dead woody fuels and live surface fuels dominate.
Parameter Estimation of Base–Age Invariant Site Index Models: Which Data Structure to Use?—A Discussion
Authors: Cieszewski Chris J. , Strub Mike 
Published: April 2024

Abstract
We discuss here methods of comparing various approaches to site-dependent height–age model-parameter estimation. The discussion emphasis is on proper analysis of the varying parameter (VP) method versus several variants of the algebraic difference methods including one with the error in variable (EIV) theory adaptation. The study has demonstrated that, when properly considered, the VP method consistently outperforms all the other methods including the EIV method. The EIV method was tested on data with known “true model” and drastically simplified errors, and had a root mean square error (RMSE) more than 10 times worse than the VP method. All the other methods produced drastically and uniquely differing results with RMSEs varying from 26 times greater than the VP method to 300 times greater. The patterns of relatively close similarity between the EIV and the VP methods and the large differing among the other methods was similar for fittings to real data of second-rotation loblolly pine (Pinus taeda L.) from a designed experiment. The VP method is recommended for use over all the other methods as the most unbiased and as much simpler than the EIV method, which was second best.
Scaling Taper Relationships from Miniature-Scale to Operational-Scale Stands of Loblolly Pine
Authors: Sharma Mahadev , Burkhart Harold E. , Amateis Ralph L. 
Published: April 2024

Abstract
Taper relationships for trees grown in miniature- and operational-scale stands of loblolly pine were established using stem analysis data from 106 and 173 trees, respectively. Tree taper was modeled using segmented polynomial and dimensionally compatible taper equations. The relationship was then scaled from miniature to operational scale using the profiles obtained from these taper equations. Stump diameter was used in the taper equations instead of dbh in scaling the relationship. A simple linear regression equation described well the taper relationship between trees grown at miniature and operational scales. The fit statistics for both the segmented polynomial and dimensionally compatible taper equations were comparable at both scales. In terms of predictive accuracy, however, the segmented polynomial taper equation was superior to the dimensionally compatible taper equation in scaling the taper relationship for trees from miniature- to operational-scale plots.