bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clonal Variation in Susceptibility of White Birches (Betula Spp.) to Mammalian and Insect Herbivores
Authors: Rousi Matti , Tahvanainen Jorma , Henttonen Heikki , Herms Daniel A. , Uotila Ilari 
Published: April 2024

Abstract
Resistance of small micropropagated plantlets and seedlings of white birch (Betula pendula Roth and B. pubescens Ehrh.) to hares (Lepus timidus L.), voles (Microtus agrestis L.) and weevils (Phyllobius and Polydrosus spp.) was determined. Field and cafeteria experiments were conducted over 2 yr period at several locations near Punkaharju Forest Research Station, Eastern Finland. There were significant differences among clones and seedlots (forest seed origins) in susceptibility to hares, voles, and weevils. One of the eight clones studied in detail was resistant to most tested agents (clone 39), whereas two clones were susceptible to each agent (clones 36 and JR/1). However, there was only one significant correlation (hare vs. Polydrosusweevil) among rankings of clones in susceptibility to different pests. Generally the differences among clones were similar in different experimental situations, indicating a genetic basis to variation in resistance. No difference in the susceptibility was observed between seedlots from natural forest and micropropagated plantlets from rapidly growing plus trees, suggesting that selecting for rapid growth did not compromise resistance as predicted by some theories. For. Sci. 43(3):396-402.
Choosing Prices to Optimally Buck Hardwood Logs with Multiple Log-Length Demand Restrictions
Authors: Pickens James B. , Throop Scott A. , Frendewey James O. 
Published: April 2024

Abstract
The purpose of this article is to present a hierarchical optimization approach that selects prices which, when used in a single stem bucking optimization model, produce a specified mix of logs by grade and length. The model is developed to address the demand constrained optimal bucking situation for northern hardwoods. The demand constraints are minimum percentages needed in four log lengths [3.0 m (10 ft), 3.7 m (12 ft), 4.3 m (14 ft), and 4.9 m (16 ft)] to meet order requirements from veneer buyers. There are two levels in the hierarchical optimization system: at the lower level, a dynamic programming model is used to optimize the value of each individual tree, while the upper level is a linear programming model which finds one or more sets of prices, each used some portion of the time, that produce the required product mix in the lower level model. The hierarchical model is solved iteratively until a single set of prices satisfies all demand constraints. This approach is distinctly different than traditional approaches, which pass different information between the upper and lower level models to solve two-level optimization problems. The parameters passed in traditional approaches are shadow prices in one direction and production levels in the reverse direction. The model developed could be adapted to other species and log grading rules whenever several competing demand constraints exist. Furthermore, the approach could be adapted to a wide range of hierarchical planning applications where inputs, and therefore the production possibilities curve, are fixed and constraints apply. For. Sci. 43(3):403-413.
Relating Site-Specific Weather Data to Regional Monitoring Networks in the Lake States
Authors: Kuuseoks E. , Liechty H. O. , Reed D. D. , Dong J. 
Published: April 2024

Abstract
Meteorological variables most frequently used in ecological studies include, or are derived from, daily precipitation and air temperature. In many studies, weather data from the nearest permanent weather station are used as surrogates for on-site measurements. This study discusses the problems with this approach and illustrates methods for developing regression equations for calculating site-specific daily minimum, average, and maximum temperatures, and precipitation amount from regional monitoring information. Meteorological data were collected at four sites along a 650 km climatic gradient from Houghton County (47°N, 89°W) to Oceana County (43°N, 86°W), Michigan. Data from several National Oceanic and Atmospheric Administration (NOAA) stations within 40 km of each study site were related to measurements made at each site. Predictive ability was improved by using information from more than one NOAA station to predict on-site temperature. No increase in predictive ability resulted from including information from more than a single station when predicting precipitation. For the majority of the sites and climate variables, the best relationships were not obtained by using the nearest NOAA station; variables such as the relative distance from large bodies of water or elevation appeared to be influential. Since distance between two locations is rarely the most important factor governing the relationship between their climates, the use of the nearest weather station is not the best method to describe weather conditions on specific sites of interest. For. Sci. 43(3):447-452.
Breeding Objective for Plantation Eucalypts Grown for Production of Kraft Pulp
Authors: Greaves Bruce L. , Borralho Nuno M. G. , Raymond Carolyn A. 
Published: April 2024

Abstract
A long-term production function for unbleached eucalypt kraft pulp, incorporating all growing, harvesting, transport, and pulping costs, and variable capital and operating costs, was used to determine the economic importance of standing volume, basic density, pulp yield, and stem form. The value of each trait to breeding was defined as the relative improvement toward the objective (of minimizing total pulp cost) for a given selection intensity when selecting for each trait individually. For genetic parameters typical of eucalypts, and with the aid of simulated first-geneneration eucalypt populations, density and standing volume were the most important traits, providing the greatest savings in total pulp cost. Combined selection using density and volume provided 95% of the gains possible from an index involving all traits (density, volume, pulp yield, and form). Selection for pulp yield alone provided only 53% of the savings possible from selection for density, and improvement in stem form had negligible effect on total pulp cost. For. Sci. 43(4):465-472.
Comparing the Economic Value of Reducing Fire Risk to Spotted Owl Habitat in California and Oregon
Authors: Loomis John B. , González-Cabán Armando 
Published: April 2024

Abstract
To increase the range of natural resource values considered in the USDA Forest Service fire management analysis system, a combined telephone contact-mail booklet-telephone interview of California and New England households regarding their willingness to pay for reducing fire intensity and acres burned in California and Oregon's spotted owl habitat located in old growth forests was performed. Using a multiple bounded dichotomous choice format, annual willingness to pay of $79 per California household and $46 per New England household was estimated for a 20% reduction in acreage burned in California. For the same percentage reduction in fire in Oregon's old growth forest the value is $59 per California household and $45 per New England household. For a combined California and Oregon Program, California households would pay $95 annually, while New England households would pay $61. This illustrates the importance of national programmatic valuation of the USDA Forest Service's fire control program in old growth forests, rather than state by state surveys which miss substitution effects. This analysis also demonstrates that households benefit from and support fire protection of old growth forests in states other than their own. For. Sci. 43(4):473-482.
Uncertainty and Forest Land Use Allocation in British Columbia: Vague Priorities and Imprecise Coefficients
Authors: Ells Arlene , Bulte Erwin , van Kooten G. Cornelis 
Published: April 2024

Abstract
Recently, increasing weight has been placed on nontimber values in forest management. Both the multiple objectives and the parameters that support decision making in forestry are often imprecise and vague. In this paper, the concepts of fuzzy set theory are explained and then applied to the problem of allocating public forestland on Vancouver Island among competing land uses. Two principal sources of fuzziness are identified--those related to uncertainty in classification (specification of management objectives) and those related to uncertainty concerning how actions affect objectives (imprecise technical coefficients). By comparing the results of classical and fuzzy decision models, we conclude that the latter approach can be judged an improvement over the former. The fuzzy land-use allocation appears to be more consistent with the political decision making process, which relies on consultation and consensus-seeking among various interest groups, that has evolved in British Columbia. The analysis also yields insights into the robustness of outcomes and suggests priority areas for further research. For. Sci. 43(4):509-520.
Genetic Parameters and Selection Efficiencies in Resistance to Western Gall Rust, Stalactiform Blister Rust, Needle Cast, and Sequoia Pitch Moth in Lodgepole Pine
Authors: Wu Harry X. , Ying Cheng C. 
Published: April 2024

Abstract
Genetic variances, heritabilities, and between-trait genetic correlations in resistance to western gall rust (Endocronartium harknessii), stalactiform blister rust (Cronartium coleosporioides), needle cast (Lophodermella concolor), and sequoia pitch moth (Synanthedon sequoiae) (Lepidoptera: Sesiidae) were investigated in a 21-yr-old lodgepole pine (Pinus contorta spp. latifolia) provenance-family trial with 778 wind-pollinated families in interior British Columbia. Selection efficiencies in expected improvement in resistance were compared among mass, family, sequential family-and-within-family, and combined family/individual index selection. Efficiencies in multitrait selection for overall resistance to the four pests based on different selection indices were also compared. Individual heritability for incidence of western gall rust was 0.50, stalactiform blister rust 0.32, needle cast 0.30, and sequoia pitch moth 0.21. Family mean heritabilities ranged from 0.39 to 0.65. The genetic correlation between incidence of sequoia pitch moth and stalactiform blister rust was 0.89, and between pitch moth and western gall rust 0.25. The genetic gain estimates from mass selection for resistance to the four pests varied from 14 to 31% at a 13% selection rate. On average, combined family/individual index selection was 5% more efficient than mass selection, and family and sequential family-and-within-family selection was about 38% and 16% less efficient than mass selection, respectively. Substantial improvement can also be expected from provenance selection. Multitrait index selection for overall resistance excluding sequoia pitch moth data was nearly as efficient as the full index. Indirect selection for resistance to sequoia pitch moth based on resistance for stalactiform blister rust was more efficient than direct selection. Selection for resistance showed little adverse effect on growth. For. Sci. 43(4):571-581.
Notes: Optimal Economic Selection of Road Design Standards for Timber Harvesting Operations―A Corrected Analytical Model
Authors: Greulich Francis E. 
Published: April 2024

Abstract
A theoretical development is given that corrects a long-accepted analytical model used in road system design. The model assumes that a forested area with uniform conditions of road construction is to be accessed by truck road for timber harvest. A discrete number of specified road design standards are available. Each design standard has known costs per unit length associated with road construction and use. The resulting total cost for any segment of the road when constructed to a given standard and used for timber haul depends fundamentally on the volume of timber transported over that segment. Transported volumes may vary along the length of the road, however, thus changing the associated costs. The emended economic decision rules for specifying road standards along the entire length of the road even as haul volumes change are developed. Examples are given. For. Sci. 43(4):589-594.
Estimating Tree Grades for Southern Appalachian Natural Forest Stands
Authors: Prestemon Jeffrey P. 
Published: April 2024

Abstract
Log prices can vary significantly by grade: grade 1 logs are often several times the price per unit of grade 3 logs. Because tree grading rules derive from log grading rules, a model that predicts tree grades based on tree and stand-level variables might be useful for predicting stand values. The model could then assist in the modeling of timber supply and in economic optimization. Grade models are estimated for ten species groups found in the southern Appalachians, using data from several thousand trees and permanent plots in the USDA Forest Service's Forest Inventory and Analysis (FIA) database. The models correctly predicted grades of a majority of trees in both a test and a validation data set, and predictions of grade proportions across a sample of the population were usually within three percentage points of actual grade proportions. But success of models varied across species and diameter groups. Considering several measures of modeling success, the most accurate models were those predicting tree grades for softwoods and larger hardwoods. For. Sci. 44(1):73-86.
Modeling Thinning Effects on Ring Specific Gravity of Loblolly Pine (Pinus taeda L.)
Authors: Tasissa Gudaye , Burkhart Harold E. 
Published: April 2024

Abstract
Effects of thinning on ring specific gravity in loblolly pine trees were examined in a regional trial in the southeastern United States. The thinning study consisted of two treatment levels (30% and 50% of the basal area removed) and a control. Thinning did not alter the proportion of the annual ring in earlywood or latewood and thus did not affect ring specific gravity. There was regional variation in average ring specific gravity, with trees from the Coastal Plain having higher ring specific gravity than trees from the Piedmont or the Highlands. Within the Coastal Plain, trees in the Gulf Coastal Plain tended to have higher average ring specific gravity than trees in the Atlantic Coastal Plain. A ring specific gravity prediction model was developed based on ring position, tree, stand, and site attributes. Much of the variation in ring specific gravity was due to within-tree variation; consequently, stand and site factors accounted for a limited proportion of variation in ring specific gravity. As the within-tree observations used in the study tended to be correlated, a direct covariance modeling approach was used to account for the correlation among observations. For. Sci. 44(2):212-223.
Qualitative Comparative Analysis: A Useful Tool for Research into Forest Policy and Forestry Conflicts
Authors: Hellström Eeva 
Published: April 2024

Abstract
The internationalization of the forestry debate and forest policy brings about a growing need to develop, apply, and discuss comparative methodologies in forestry research. This paper illustrates and discusses the use of Qualitative Comparative Analysis (QCA), a new comparative tool in forest policy research. The advantages and disadvantages of the method are demonstrated by reanalyzing previous research on public environmental criticism of forestry in Finland, Sweden, Norway, West Germany, France, and the United States between 1950 and 1983. In particular, the reanalysis illustrates the potential benefits of systematic techniques of comparison as supplementary tools to traditional "common sense" interpretations of qualitative data. In addition to arguing on behalf of the technical applicability of the method to comparative forest policy research, a need is expressed to expand the use of the method from causal to noncausal applications. For. Sci. 44(2):254-265.
Forest Harvests and Wood Products: Sources and Sinks of Atmospheric Carbon Dioxide
Authors: Winjum Jack K. , Brown Sandra , Schlamadinger Bernhard 
Published: April 2024

Abstract
Changes in the net carbon (C) sink-source balance related to a country's forest harvesting and use of wood products is an important component in making country-level inventories of greenhouse gas emissions, a current activity within many signatory nations to the UN Framework Convention on Climate Change. We propose two approaches for estimating national C inventories from forest harvesting and wood product utilization (excluding forest regrowth): the atmospheric-flow method and the stock-change method. The former has the atmosphere as its system of interest and counts all flows to and from the atmosphere for a particular country. The latter looks at a country's forest and wood product C stocks and how they change over time. Here we develop these two methods, and estimate national C source-sink balance from the readily available FAO global forest products database for countries, regions, and the world. Both methods gave a worldwide estimated source of 980 Tg of C in 1990 as a result of forest harvests and wood product utilization; about 60% came from developing countries and 40% from developed countries. Estimates (Tg C) for selected developing countries for the atmospheric-flow/stock-change method were: Brazil, 72/73; India, 81/80; Indonesia, 53/56; and Ivory Coast, 3.9/4.3; and for selected developed countries (again atmospheric-flow/stock-change method): Canada, 36/50; Finland, 8.8/13; New Zealand, 2.7/3.4; and United States 141/138. Net wood exporters show lower numbers in the atmospheric-flow method, net wood importers in the stock-change method. Among the variables that most consistently and strongly affected C emissions for a given country in 1990 were: roundwood production, slash left to oxidize, and commodity wood put into uses ≥ 5 yr. We conclude with a discussion that shows how choosing either one of the two methods for wood harvest accounting has potential policy implications or impacts on the incentives or disincentives to use wood. For. Sci. 44(2):272-284.
Measuring the Efficiency of Public Forestry Organizations
Authors: Viitala Esa-Jussi , Hänninen Harri 
Published: April 2024

Abstract
The decreasing budgets of public forestry organizations have given rise to the present need to evaluate their efficiency and to find means to improve it. In this paper the efficiency of 19 state-funded, regional Forestry Boards is investigated using Data Envelopment Analysis (DEA). In addition, the prime determinants of efficiency are examined using Tobit models. The results indicate a substantial variation in efficiency across Forestry Boards with a potential for input saving in the range of 20%. It seems that, of the controllable factors, management style and support are associated with efficiency. It appears also that applying DEA with Tobit models provides a useful two-stage approach to assess and explain efficiency differences among public forestry organizations. For. Sci. 44(2):298-307.
Influence of Intensive Culture on Leaf Net Photosynthesis and Growth of Sweetgum and Loblolly Pine Seedlings
Authors: Samuelson L. J. 
Published: April 2024

Abstract
The influence of (1) complete weed control only, (2) weed control and irrigation, (3) weed control and irrigation with a fertilizer solution (fertigation), and (4) weed control and fertigation plus pest suppression (pine only) on midday light-saturated leaf net photosynthesis (Pn) of sweetgum (Liquidambar styraciflua L.) and loblolly pine (Pinus taeda L.) was examined monthly, two growing seasons after plantation establishment. Irrigation but not fertigation increased Pn on all dates and more than doubled height and diameter of sweetgum after the first growing season. Greater Pn in sweetgum in response to irrigation was, in part, a result of reductions in stomatal limitation to Pn and decreased stomatal sensitivity to vapor pressure deficit. In loblolly pine, Pn was increased only by irrigation and only on one date during the first growing season. No effect of treatment on Pn of either species was observed for the second season. After two growing seasons, an eight-fold increase in aboveground biomass and six-fold increase in leaf area were observed in sweetgum in response to fertigation relative to the control treatment. Fertigation plus pest control treatment eliminated tip moth damage to shoots of loblolly pine during the first growing season and resulted in a doubling of total biomass and tripling of leaf area. Maximum biomass accumulation in sweetgum and loblolly pine after two seasons of intensive culture was mainly a function of leaf area rather than Pn For. Sci. 44(2):308-316.
Segmenting the Market for Environmentally Certified Wood Products
Authors: Ozanne Lucie K. , Smith Paul M. 
Published: April 2024

Abstract
A study was conducted to segment consumers in terms of their attitudes toward environmentally certified wood products. Factor analysis reduced seven variables of environmental certification to two distinct factors. Cluster analysis, performed on the seven variables of forest and wood products certification, suggested the existence of six relatively homogeneous groupings or segments of consumers. Multiple discriminant analysis provided a method for profiling these six consumer segments in terms of demographic, attitudinal, and trust (respondent's trust in potential certifying organizations) variables. This paper identifies one consumer segment of approximately 25 million Americans who would most likely seek out environmentally certified wood products. Relative to our other study respondents, they can be described as politically liberal, Democrats, female, members of an environmental organization, fairly well educated, concerned about the quality of the environment and forest resources, and having high self-rated environmental knowledge. In addition, these respondents would place the most trust in the certification claims made by an environmental organization. Conversely, a consumer segment of nearly 10 million Americans appears highly skeptical of certification programs, in general. Consistent with previous literature, our demographic variables were less effective in discriminating among groupings of consumers than attitudinal and trust variables. Implications of segmentation strategies are discussed for both industrial managers and forest policymakers. For. Sci. 44(3):379-389.
Impact of Alternative Regeneration Methods on Genetic Diversity in Coastal Douglas-Fir
Authors: Adams W. Thomas , Zuo Jinghua , Shimizu Jarbas Y. , Tappeiner John C. 
Published: April 2024

Abstract
Genetic implications of natural and artificial regeneration following three regeneration methods (group selection, shelterwood, and clearcut) were investigated in coastal Douglas-fir (Pseudotsuga menziesii var. menziesii [Mirb.] Franco) using genetic markers (17 allozyme loci). In general, harvesting followed by either natural or artificial regeneration resulted in offspring populations little altered from those in the previous generation. Cutting the smallest trees to form shelterwoods, however, resulted in the removal of rare, presumably deleterious, alleles, such that slightly fewer alleles per locus were observed among residual trees (2.76) and natural regeneration (2.75) than found in uncut (control) stands (2.86). Thus, although the shelterwood regime appears quite compatible with gene conservation, it would be best to leave parent trees of a range of sizes in shelterwoods designated as gene conservation reserves, in order to maximize the number of alleles (regardless of current adaptive value) in naturally regenerated offspring. Seedling stocks used for artificial regeneration in clearcut, shelterwood, and group selection stands (7 total) had significantly greater levels of genetic diversity, on average, than found in natural regeneration. This is probably because the seeds used in artificial seedling stocks came from many wild stands and thus, sampled more diversity than found in single populations. For. Sci. 44(3): 390-396.