bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic Variation Among and Within Single-Tree Progenies of Northern Red Oak
Authors: Kolb T. E. , Steiner K. C. 
Published: April 2024

Abstract
Twelve genotypes from each of five open-pollinated families of northern red oak (Quercus rubra L.) were clonally multiplied by splitting embryos from seeds. Height and stem diameter were measured on all clones over two growing seasons in outdoor planters. Families, and clones from the same family, differed significantly in first- and second-year height and diameter adjusted to the same seed weight. Clone-within-family variance was greater than family variance for first-year height (53% versus 35% of total variance), while family variance was greater than clone-within-family variance for second-year height (40% versus 35%). For. Sci. 35(1):pp. 251-256.
Root System Structure in Planted and Seeded Loblolly and Shortleaf Pine
Authors: Harrington Constance A. , Brissette John C. , Carlson William C. 
Published: April 2024

Abstract
Differences in root system structure attributable to stand origin were examined by pairing seeded and planted stands of loblolly (Pinus taeda L.) and shortleaf pine (P. echinata Mill.). The 17 paired stands were 3 to 9 years old and located in Arkansas, Oklahoma, and Texas on similar soil and site conditions. Root systems from 12 trees were excavated from each stand, classified by root system type and measured for number and size of first-order lateral roots and amount of root spiraling and bending. Although root systems of planted trees were commonly deformed, the most consistent difference in root system structure between planted and seeded trees was the increased distance from groundline to the uppermost lateral roots on planted seedlings. A linear discriminant function including this variable correctly classified all loblolly pine plots and 89% of the shortleaf pine plots as to whether the plot had been planted or seeded. Planted trees also had fewer first-order lateral roots less than 10 mm in diameter and exhibited greater spiraling and bending of major first-order laterals than seeded trees. Differences in root system structure between planted and seeded trees were similar for the two species. For. Sci. 35(2):469-480.
A Production Function Analysis of Loblolly Pine Yield Equations
Authors: Liu Chiun-Ming , Leuschner William A. , Burkhart Harold E. 
Published: April 2024

Abstract
A timber production function analysis for unthinned loblolly pine plantations was made using a four-equation system. In the system, the yield equation is the production function. The production function and other equations fit the data well, using biological consistency, significance, goodness of fit, and minimal collinearity as criteria. The system also predicted volume for lightly and heavily thinned stands with a Mean Difference of 2 and 5% of mean volume, respectively. Analysis of the production function coefficients verified the functional form. More specifically, all input factors are complementary, output elasticities indicate a relatively unresponsive production function, the Elasticity of Scale is 2.3, the elasticities of substitution lie between zero and 1.0, and the production function has Variable Elasticity of Substitution (VES). For. Sci. 35(3):775-788.
An Economic Analysis of Harvest Behavior: Integrating Forest and Ownership Characteristics
Authors: Dennis Donald F. 
Published: April 2024

Abstract
This study provides insight into the determinants of timber supply from private forests through development of both theoretical and empirical models of harvest behavior. A microeconomic model encompasses the multiple objective nature of private ownership by examining the harvest decision for landowners who derive utility from forest amenities and from income used for the consumption of other goods. Tobit analysis is used to estimate the relationship between harvest behavior and forest, owner, and economic characteristics from cross-sectional data for individual forest plots in New Hampshire. The empirical results highlight the influence of forest characteristics and landowner affluence on the harvest decision. Decomposition of the Tobit coefficients indicates that changes in timber supply are expected to result primarily from changes in the number of acres from which timber is offered for sale and to a much lesser extent from changes in per-acre harvesting intensity. Marginal supply responses varied considerably depending on the values for the other coefficients and variables, underscoring the need to consider the shape of the distribution as well as the mean values for the explanatory variables when projecting harvest behavior. For. Sci. 35(4): 1088-1104.
Biomass Estimation Methods for Tropical Forests with Applications to Forest Inventory Data
Authors: Brown Sandra , Gillespie Andrew J. R. , Lugo Ariel E. 
Published: April 2024

Abstract
This paper contains a strategy for estimating total aboveground biomass of tropical forests. We developed regression equations to estimate aboveground biomass of individual trees as a function of diameter at breast height, total height, wood density, and Holdridge life zone (sensu Holdridge 1967). The regressions are applied to some 5,300 trees from 43 independent sample plots, and 101 stand tables from large-scale forest inventories in four countries, to estimate commercial and total aboveground biomass per unit area by forest type, and to estimate expansion factors defined as the ratio of aboveground to commercial biomass. The quadratic stand diameter (QSD, i.e., the diameter of a tree of average basal area) in a given forest stand influences the magnitude of the expansion factor. Stands of small trees have large expansion factors (up to 6.4), and as QSD increases, the expansion factor decreases to a constant value (about 1.75). For undisturbed forests in moist, moist transition to dry, and dry life zones respectively, the expansion factors for total aboveground biomass were 1.74, 1.95, and 1.57 respectively. For undisturbed, logged, and nonproductive forest categories used by the FAO to report global commercial wood volume data, we estimated expansion factors of 1.75, 1.90, and 2.00 respectively. Applying these factors to FAO data results in a 28 to 47% increase in previous volume-derived estimates of tropical forest biomass. However, estimates of tropical forest biomass based on small destructive samples continue to be high relative to estimates based on volume data. For. Sci. 35(4):881-902.
Controls over Net Inorganic Nitrogen Transformations in an Age Sequence of Pinus Elliottii Plantations in North Florida
Authors: DiStefano J. F. , Gholz H. L. 
Published: April 2024

Abstract
The controls over net ammonification and net nitrification in recently clearcut, 9-year-old and 29-year-old plantations of Pinus elliottii in north Florida were investigated using a combination of field (in situ) and laboratory soil incubations. Fertilization with PK and NPK and prescribed burning were also used in the field to further determine effects of P and NH+4-N availability on net N transformations. Results revealed complex relationships among N availability and plantation age, incubation method, season and treatment. Ammonification rates were generally lower than those found in other studies. The clearcut, 9-year-old and NPK-fertilized plots had the greatest rates. The single burns and PK-fertilization had little effect on rates, although soil chemistry was significantly altered. Net nitrification rates were negligible except on the NPK-fertilized plots, which had greatly elevated rates of both net ammonification and net nitrification. We conclude that P availability had little apparent affect on net N transformations in the surface soil and that N availability was least in the oldest stand. For. Sci. 35(4):920-934.
Optimizing Any-Aged Management of Mixed-Species Stands: II. Effects of Decision Criteria
Authors: Haight Robert G. , Monserud Robert A. 
Published: April 2024

Abstract
The effects of maximum present value and maximum volume objectives on the efficiencies of alternative silvicultural systems are determined by solving any-aged management problems for mixed-conifer stands in the Northern Rocky Mountains. Any-aged management problems are formulated with periodic planting and harvesting controls and without constraints on the stand age or size structure over time. Optimization is performed with the Stand Prognosis Model, a single-tree simulator that has been calibrated for many forest types in the western United States. With a maximum present value objective, 1987 stumpage prices, and no logging damage, steady-state, uneven-aged management using selection cuts is the target silvicultural system for a range of stand types. Optimal transition regimes for understocked stands include clearcutting and planting western white pine (Pinus monticola Dougl. ex D. Don), a high-value, fast-growing species. With a maximum merchantable volume objective, two types of management emerge as optimal: even-aged plantation management and an uneven-aged shelterwood system are both capable of producing the same high level of yield indefinitely. Both types of management rely on a series of thinnings to grow the most vigorous crop trees into the largest size classes. In addition, the shelterwood system ensures that adequate natural regeneration is established when the crop trees are harvested. Because the uneven-aged shelterwood system produces steady-state yields that are as high or higher than plantation management, these results call into question the widely held view that even-aged plantation management maximizes total merchantable volume production. For. Sci. 36(1):125-144.
König-Faustmannism: A Critique
Authors: Oderwald Richard G. , Duerr William A. 
Published: April 2024

Abstract
The König-Faustmann form of marginal analysis derives a valid estimate of the financially optimal rotation for individual trees and other indivisible forest capital: forests whose age-class structure is not to be changed. For divisible capital, the applicable form of the marginal model derives a shorter rotation because it allows for interactions among forest compartments. For. Sci. 36(1):169-174.
Evaluation of Four Estimators of Herbicide Treatment Efficacy for Woody Competition Control Studies
Authors: Knowe Steven A. , Shiver Barry D. , Borders Bruce E. 
Published: April 2024

Abstract
Four estimators of herbicide treatment efficacy based on hardwood crown measurements were evaluated. Using data from untreated plots, expected post-treatment size of treated hardwood rootstocks was obtained by accounting for growth between pre- and post-treatment evaluations with an unadjusted mean, a ratio-of-means estimator, and a regression estimator. Formulas were developed to compare the estimates of hardwood control based on change in crown size relative to pretreatment size, unadjusted mean post-treatment size, and ratio- and regression-adjusted post-treatment size. Conditions for optimum application of the estimators were also discussed. The effects of all four estimation procedures on the estimated means and treatment contrasts were demonstrated for flowering dogwood (Cornus florida L.) and sweetgum (Liquidambar stryaciflua L.) in a site-preparation study located in the Georgia piedmont. The lowest mean control was obtained using change in crown size, while control based on regression-adjusted crown size resulted in the highest mean control. Treatment contrasts for control based on change in crown size and control based on ratio-adjusted crown size had the same level of significance for both species. For dogwood, all four estimators of efficacy resulted in the same conclusion (acceptance or rejection of the null hypothesis) for 8 of 9 contrasts, although regression-based control tended to be the most conservative. For sweetgum, the null hypothesis of no differences among treatments was rejected more frequently using efficacy based on the unadjusted mean post-treatment crown size or regression-adjusted post-treatment crown size. A regression estimator of post-treatment crown size appears to be more flexible in its application than ratio-adjusted estimates. For. Sci. 36(2):201-211.
Heating-Related Water Transport to Intact Lodgepole Pine Branches
Authors: Cohen Warren B. , Omi Philip N. , Kaufmann Merrill R. 
Published: April 2024

Abstract
Woody plants may have the ability to transport water to heated foliated branches. If so, additional water vaporized could have a significant impact on energy absorbed by heated plant crowns. To investigate this, we compared energy absorbed by similar intact and detached branches of well-watered lodgepole pine trees (Pinus contorta Dougl. ex Loud.) during heating in a specially designed calorimeter.
When heated to 250°C, intact branches absorbed 49% more energy than detached branches; an amount equivalent to 0.62 g more of water per gram of dry branch vaporized from intact than from detached branches. After heating, no water remained in the detached branches, while intact branches had a mean residual water content of 10.8%. These results indicate that significant amounts of water can be transported to, and vaporized from, heated branches of non-drought-stressed lodgepole pine trees. Hence, by accounting only for the initial water contained in heated foliated branches, current fire behavior models improperly calculate energy absorption by heated woody plant crowns. For. Sci. 36(2):246-254.
An Economic Evaluation of Research on Herbaceous Weed Control in Southern Pine Plantations
Authors: Huang Y. Star , Teeter Lawrence 
Published: April 2024

Abstract
Interest in forestry research evaluation has steadily increased in recent years. This paper describes an ex ante model, which uses forecasts of the future benefits of current and proposed research to evaluate a research program that focuses on enhancing pine growth by controlling competition from herbaceous weeds. A principal value of this model is its potential for wide applicability to other forest management research programs. The method requires information describing pine growth impacts, the probability of future research success, the probability and rates of future technology adoption, the management strategies of potential users of the technology (weighted by the area and site quality of lands under their control), the costs of research extension, and technology adoption, and the future value of stumpage. Past and planned herbaceous weed control research will produce substantial net economic benefits through the application of research findings to the management of pine forest types in the southern U.S. for. Sci. 36(2):313-329.
Dating Decline and Mortality of Chamaecyparis nootkatensis in Southeast Alaska
Authors: Hennon P. E. , Shaw III C. G. , Hansen E. M. 
Published: April 2024

Abstract
Alaska yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) has been declining and dying for a long, but undetermined, span of time in remote and undisturbed forests of southeast Alaska. Aerial photographs indicate mortality was widespread by 1927. The dates of death for individual snags of Alaska yellow-cedar were determined by counting annual rings on 73 western and mountain hemlock trees growing beneath larger, dead Alaska yellow-cedars, and in live callus strips on 46 Alaska yellow-cedars with partial bole death. Average time since death was 4, 14, 26, 51, and 81 years for snags in class I (foliage retained), class II (twigs retained), class III (secondary branches retained), class IV (primary branches retained), and class V (bole intact but no primary branches retained), respectively. Class V snags, which are common on all sites currenty expressing decline, appear to represent the trees initially affected. Snags in a sixth class with deteriorating boles are uncommon and not associated with sites of decline; their death most likely predated the onset of extensive mortality. Because some class V snags died over 100 years ago, these data suggest that extensive mortality began about 1880, and became obvious about 1900-1910—dates supported by historical records. For. Sci. 36(3):502-515.
Identification of a Network Substructure and Some Algorithmic Considerations for Large-Scale Harvest Scheduling Problems
Authors: Sherali Hanif D. , Liu Chiun-Ming 
Published: April 2024

Abstract
Berck and Bible (1984) have suggested a solution approach for harvest scheduling problems based on the Dantzig-Wolfe (1960) decomposition algorithm. We first expose the fact that the area constraints in their problem possess a network structure, requiring the solution of a single longest path problem, and show that the elegant dosed-form solution derived by Berck and Bible is precisely a readily obtained longest path solution. Moreover, we show that when additional variable bounds are imposed, the network structure remains exploitable. Second, we compare the computational effort and storage requirements of the Dantzig-Wolfe algorithm and the revised simplex method for solving this problem. The slow tail-end convergence of the Dantzig-Wolfe approach is of particular concern. However, we provide operational guidelines showing when this procedure may be preferred. Other viable algorithms suitable for solving this problem are also discussed. For. Sci. 36(3):599-613.
Considerations on Modeling the Market for Softwood Lumber in the United States
Authors: Uri Noel D. , Boyd Roy 
Published: April 2024

Abstract
This paper uses the Granger causality test to determine whether the demand for softwood lumber affects price in the current period or subsequent periods, or whether price is exogenous. This test is run for each of four geographically distinct regions in the United States. Further statistical tests are then used to detect the geographical extent of the softwood lumber market. The results indicate that demand is indeed strongly connected to prices, and that there is a national market for softwood lumber. For. Sci. 36(3):680-692.
Identifying Trees in Riparian Areas That Can Provide Coarse Woody Debris to Streams
Authors: Robison E. George , Beschta Robert L. 
Published: April 2024

Abstract
The natural fall of trees into mountain streams provides coarse woody debris that can improve fish habitat and influence stream morphology. Geometric and empirical equations, based on tree size and distance from the stream, were used to determine the conditional probability of a tree's adding coarse woody debris to a stream. Additional equations were developed to relate this probability to basal area factor. For conditions in the Pacific Northwest, Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) was selected to illustrate how the equations can be used for varying tree sizes and probabilities. After selecting a probability and determining basal area factor by these equations, resource managers can use prisms or wedge devices before timber harvesting in riparian areas to identify specific trees that can potentially add woody debris to the stream. For. Sci. 36(3):790-801.
Relationships Between Site Index and Synoptic Environmental Factors in Immature Coastal Douglas-Fir Stands
Authors: Klinka K. , Carter R. E. 
Published: April 2024

Abstract
Indirect synoptic measures of climate, soil moisture, and soil nutrients are used to characterize site quality in the biogeoclimatic ecosystem classification. To assess relationships of these measures to potential forest productivity, environmental and site index data from 133 sample plots established in immature coastal Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) stands were utilized. The stands were distributed across three climatic regimes (biogeoclimatic units), five soil moisture regimes, and five soil nutrient regimes. These regimes were used as categorical variables in stratification of the data and regression analysis.
Direct measures of these regimes, i.e., components of annual water balance and mineralizable-N in the forest floor and mineral soil, were determined for each stand and used as continuous variables in regression analysis. Douglas-fir site index (m/50 yr) and these direct measures were significantly different between groups of stands stratified according to soil moisture and soil nutrient regimes. Five regression models indicated good relationships between site index and both categorical and continuous variables. The analytical models (based on actual evapotranspiration during May and June, growing season water deficit, and/or mineralizable-N in the forest floor and mineral soil) were slightly inferior (R² = 0.72) to the categorical models (based on soil moisture and nutrient regimen (R² = 0.84). Testing on an independent data set showed similar results, i.e., the categorical models continued to have a better relationship with site index than the analytical models. It is concluded that the indirect synoptic measures of climate, soil moisture and soil nutrients were good predictors of Douglas-fir site index over a large area and provided useful estimates of the direct measures. For. Sci. 36(3):815-830.
Adaptation of Acacia koa Leaves and Phyllodes to Changes in Photosynthetic Photon Flux Density
Authors: Walters Gerald A. , Bartholomew Duane P. 
Published: April 2024

Abstract
Koa (Acacia koa Gray) seedlings were grown under full sunlight (HH treatment) and under 27% of full sunlight (LL treatment). Some of these seedlings were moved to the opposite light intensity to form two additional treatments--HL and LH. Phyllodes developed only on seedlings in the HH treatment. If seedlings with phyllodes were placed under shade, leaves instead of phyllodes developed at the terminal. Leaflets of leaves in the HH treatment were smaller but thicker and had lower specific leaf areas than those in the LL treatment. Koa leaves in the HH and LL treatments had similar photosynthetic characteristics. Leaves in the HH treatment had higher ribulose 1,5-bisphosphate carboxylase levels and lower chlorophyll levels than leaves in the LL treatment. When seedlings were moved to the opposite light intensity, leaves and phyllodes adapted both morphologically and physiologically to the altered photosynthetic photon flux density (PPFD). Leaves and phyllodes that were only partially developed when the PPFD changed showed greater adaptive potential than those that were fully developed. Generally, leaves and phyllodes adapted by developing morphological and physiological characteristics of those grown continuously in the new PPFD. There were no detectable deleterious affects to exposing leaves or phyllodes to increased or decreased PPFDs For. Sci. 36(4):1050-1060
Stumpage Prices in Southwestern Ontario: A Hedonic Function Approach
Authors: Puttock G. D. , Prescott D. M. , Meilke K. D. 
Published: April 2024

Abstract
Timber used in the production of lumber in Southwestern Ontario varies in a number of characteristics, and the lump-sum stumpage price is expected to reflect differences in those characteristics. When heterogeneous inputs are used in production, the hedonic price function approach may be used to estimate marginal implicit values of the various input characteristics. Hedonic price functions were estimated for timber in Southwestern Ontario using pooled time-series cross-section data from a large sample of timber sales. The results indicate that volume, species composition, tree size, timber quality and distance to the purchasing mill all affect lump-sum stumpage prices. Estimates of the contributions that each of these characteristics makes to stumpage prices are presented. The estimated hedonic model was tested by comparing the model's forecasts of stumpage prices with forecasts made by personnel from the Ministry of Natural Resources. For. Sci. 36(4):1119-1132.