bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predictive Posterior Distributions from a Bayesian Version of a Slash Pine Yield Model
Authors: Green Edwin J. , Strawderman William E. 
Published: April 2024

Abstract
We formulate a traditional slash pine diameter distribution yield model in a Bayesian framework. We attempt to introduce as few new assumptions as possible. We generate predictive posterior samples for a number of stand variables using the Gibbs sampler. The means of the samples agree well with the predictions from the published model. In addition, our model delivers distributions of outcomes, from which it is easy to establish measures of uncertainty, e.g., Bayesian credible regions. For. Sci. 42(4):456-464.
Long-Run Timber Supply and the Economics of Timber Production
Authors: Yin Runsheng , Newman David H. 
Published: April 2024

Abstract
The analysis of long-run timber supply is hampered by the lack of a well-defined profit function. Such a function provides the foundation for deriving a theoretically consistent supply equation. Some recent studies have attempted to obtain a timber supply equation by manipulating the stand-level Faustmann model. As a result of inappropriate approaches and assumptions, their conclusions may be false. In this article, we build on the Faustmann-Smith-Samuelson model first developed by Comolli (1981) to examine aggregate timber production. We show this model to have the desired properties of a profit function that allows us to test various issues. It is then found that the general beliefs of negatively sloped per-land-unit supply curves and positively sloped aggregate supply curve are robust. Finally, we present several applications and implications of our modeling approach. For. Sci 43(1):113-120.
Stochastic Models for Conifer Tree Crown Profiles
Authors: Biging Gregory S. , Gill Samantha J. 
Published: April 2024

Abstract
We perform a feasibility study of using stochastic models to describe the profile of tree crowns and to capture the stochastic nature of the tree crown form for five conifer species of the Sierra Nevada. In 70% of the cases investigated we found that we could model tree crown profiles as a quadratic or cubic trend in conjunction with a simple autoregressive moving average model (ARMA). In the remaining cases we used a quadratic or cubic trend in conjunction with white noise. These stochastic ARMA models are visually and statistically an improvement over using Euclidean geometric crown profile models. Competing models were judged by using Akaike's Information Criterion (AIC) to achieve a parsimonious model. It was found that first-order moving average MA(1) models or first-order autoregressive AR(1) models were adequate for modeling the majority of the cases studied and that these models were qualitatively similar. MA(1) models were preferred over the AR(1) models because less information is required to simulate them. For. Sci. 43(1):25-34.
Leaf Area-Productivity Relationships Among Mixed-Species Hardwood Forest Communities of the Central Hardwood Region
Authors: Jose Shibu , Gillespie Andrew R. 
Published: April 2024

Abstract
A study was conducted to quantify the influence of environmental factors on the leaf area-productivity relationships of Ecological Land Type Phases (ELTPs) representing Central Hardwood forest communities. Forest inventory data were collected from 83 plots taken along a moisture gradient, stratified within recognized ELTPs in the Hoosier National Forest in southern Indiana. Density (standing basal area, volume, and biomass), annual production, leaf area index (LAI), and water balance indices were determined for each ELTP. Ecological Land Type Phases showed marked differences in density and growth measures which were positively correlated with leaf area index. Leaf area index, in turn, exhibited strong correlations with site and environmental factors. Further, a reduction in canopy-average specific leaf area with decreasing soil moisture and LAI was observed. In general, maximum growth efficiency (measured as growth per unit of LAI) was attained at a LAI of approximately 3.5, after which it decreased. However, no significant differences in growth efficiency were found among ELTPs, suggesting that the communities were adjusting to differences in resource availability, particularly water. Thus, these mixed-species forest communities adjust both species composition and canopy morphology to compensate for changing environmental gradients. For. Sci. 43(1):56-64.
Effects of Constitutive and Inducible Traits of Hybrid Poplars on Forest Tent Caterpillar Feeding and Population Ecology
Authors: Robison Daniel J. , Raffa Kenneth F. 
Published: April 2024

Abstract
Hybrid Populus spp. clones, differentially affected forest tent caterpillar, Malacosoma disstria, behavior, development, and population dynamics. Increased larval cohort size and larval silk generally enhanced development. Larval behavior affected developmental success. Under choice conditions, larvae selected more suitable clones, and their growth was enhanced when they moved from less to more suitable hosts. Herbivory by the forest tent caterpillar caused significant reductions in the quality of foliage for subsequent larval development. Polar and nonpolar foliar extracts varied between constitutive and previously damaged plants, and elicited significant larval behavioral responses. The extent to which prior feeding induced foliar changes that affected larval feeding and development varied among clones. The ability of forest tent caterpillar to exploit clones includes genetic and environmental components affecting foliar quality, and includes positive and negative density dependent feedback. In whole-tree field cages, forest tent caterpillar populations increased 9.7x during a 2 yr period on a highly suitable clone, and declined 2.7x on a poor quality clone. The relationships between clonal suitability and forest tent caterpillar population growth were strongly influenced by bud phenology and exudates, in addition to foliar traits. For. Sci. 43(2):252-267.
Growth, Development, and Yield in Pure and Mixed Stands of Eucalyptus and Albizia
Authors: Debell Dean S. , Cole Thomas G. , Whitesell Craig D. 
Published: April 2024

Abstract
Productivity of Eucalyptus saligna Sm. plantations is commonly limited by low levels of available nitrogen (N), and synthetic N fertilizer applications are costly and sometimes impractical; thus, we evaluated mixed species plantings in which N is added by Albizia falcataria (L.) Fosberg [=Paraserianthes falcataria (L.) Nielson]. Five ratios of Eucalyptus and Albizia were compared with each other, with pure Albizia, and with pure Eucalyptus fertilized periodically with N in a randomized block design on the wet Hamakua coast of the Island of Hawaii. Eucalyptus growth increased as the amount of Albizia in the stand increased from 11 to 66%, and heights and diameters of Eucalyptus in stands containing 34% or more Albizia were equal to or larger than those in fertilized, pure stands. Total aboveground biomass, stem biomass, and stem volume per ha of mixed stands at age 10 were at least equal to yields produced in fertilized, pure Eucalyptus stands; total biomass of mixed stands with 50 or 66% Albizia was 30 and 46% greater than that in fertilized, pure Eucalyptus and 10 and 24% greater than that of pure Albizia. Yield of the Eucalyptus component alone in these two mixtures was at least equal to that of fertilized, pure Eucalyptus stands. Moreover, mean annual increment declined more slowly after culmination in all-mixed stands than in the fertilized, pure Eucalyptus stand. Over time, the apparent benefits of mixed versus pure plantings of Eucalyptus and Albizia have increased, and at age 10 include diversity in stand structure (and habitat) as well as the improvements in Eucalyptus tree growth and stand productivity recognized at younger ages. For. Sci. 43(2):286-298.
Constraining Individual Tree Diameter Increment and Survival Models for Loblolly Pine Plantations
Authors: Zhang Shaoang , Amateis Ralph L. , Burkhart Harold E. 
Published: April 2024

Abstract
Among extant forest growth and yield models, individual tree growth models provide the most detailed information, which is useful for intensive forest management. However, individual tree growth models may be inaccurate for stand-level predictions because of the cumulative error resulting from individual tree predictions. This paper is aimed at developing a method to ensure that individual tree growth models not only provide precise individual tree predictions but also give precise stand-level estimation. Based on the conceptual relationships between basal area of each diameter class and the diameter increment of trees in the same diameter class, a constrained regression equation system is proposed. The same approach is also applied to modeling individual tree survival probability. An algorithm for estimating multiresponse regressions was developed. Results using data from unthinned loblolly pine (Pinus taeda L.) plantations show that the simultaneous equation system provides nearly the same individual tree diameter increment estimates as the unconstrained model but better estimates for basal area of each diameter class and for total stand basal area. The potential for improving stand mortality estimation with a constrained individual tree survival model where there is little mortality in the data is limited. For. Sci. 43(3):414-423.
Relationship Between Volatile Foliar Terpenes and Resistance of Sitka Spruce to the White Pine Weevil
Authors: Tomlin Elizabeth S. , Borden John H. , Pierce Harold D. 
Published: April 2024

Abstract
Volatile foliar terpenes were compared both quantitatively and qualitatively among 20 provenances and 11 cloned genotypes of Sitka spruce (Picea sitchensis Bong [Carr.]) that had been classified as resistant or susceptible to the white pine weevil (Pissodes strobi [Peck]). On average, trees in resistant provenances had significantly lower content of ten terpenes than in susceptible provenances. One resistant clone had significantly higher foliar terpene content, and four resistant clones had significantly lower content than susceptible trees. Thus clonal resistance could be expressed respectively by repellency or lack of apparency. Canonical discriminant analysis revealed that several resistant clones, particularly from the Haney provenance, could be distinguished from others on the basis of their terpene profiles. While there was no clear relationship between terpene profile and resistance, these results suggest that there are probably multiple resistant "chemotypes," and that volatile foliar terpenes may be useful in identifying potentially resistant trees. For. Sci. 43(4):501-508.
Analyzing Uncertainties in Experts' Opinions of Forest Plan Performance
Authors: Alho Juha M. , Kangas Jyrki 
Published: April 2024

Abstract
Multi-objective forestry requires new decision support systems to aid the forest owner and foresters in the planning of future treatment schedules. The analytic hierarchy process (AHP), based on pairwise comparison data and Saaty's eigenvector method, is one technique that has been proposed to make such qualitatively different objectives as income from timber sales and scenic beauty of forest landscape commensurable. A weak point of the methodology has been the lack of a statistical theory behind it. We have earlier shown how classical regression techniques can be used to provide a statistical assessment of the uncertainty of the estimated ratio-scales. In this paper we extend the results to a multi-level decision hierarchy commonly used in forest planning. We also provide a Bayesian extension of the regression technique. The advantage of the Bayesian approach is that it provides summaries of expert views that are easily understood by decision makers who may not have extensive understanding of statistical concepts. On the basis of the Bayesian analysis, one can calculate, for example, how likely it is that (in the view of the expert) a given forest plan is better than any other plan being compared. For. Sci. 43(4):521-528.
Reconstructing the Spatial Pattern of Trees from Routine Stand Examination Measurements
Authors: Hanus Mark L. , Hann David W. , Marshall David D. 
Published: April 2024

Abstract
Reconstruction of the spatial pattern of trees is important for the accurate visual display of unmapped stands. The proposed process for generating the spatial pattern is a nonsimple sequential inhibition process, with the inhibition zone proportionate to the scaled maximum crown width of an open-grown tree of the same species and same diameter at breast height as the subject tree. The results of this coordinate generation procedure are compared with mapped stem data from nine natural stands of Douglas-fir at two ages by the use of a transformed Ripley's K(d) function. The results of this comparison indicate that the proposed method, based on complete tree lists, successfully replicated the spatial patterns of the trees in all nine stands at both ages and over the range of distances examined. On the basis of these findings and the procedure's ability to model effects through time, the nonsimple sequential inhibition process has been chosen to generate tree coordinates in the VIZ4ST computer program for displaying forest stand structure in naturally regenerated young Douglas-fir stands. For. Sci. 44(1):125-133.
Bayesian Analysis of the Linear Model with Heterogeneous Variance
Authors: Green Edwin J. , Valentine Harry T. 
Published: April 2024

Abstract
Linear models are among the most common statistical tools in forestry, and indeed in all science. It is widely known that when linear models are applied to attributes of size (e.g., individual tree volumes), the conditional variance may be heterogeneous. Under these circumstances, the usual least squares estimator remains consistent, but is no longer efficient. This has been appreciated in forestry for some time, and various solutions have been recommended over the years. In this paper, we propose a Bayesian solution. Bayesians would prefer this method to previous solutions for many reasons. However, even non-Bayesians may wish to consider the method as it yields (as will be shown) solutions quite close to the maximum likelihood solution, along with the marginal posterior distribution of each parameter. For. Sci. 44(1):134-138.
Long-Term Trends in Height Growth of Jack Pine in North Central Ontario
Authors: Goelz J.C. G. , Burk T. E. 
Published: April 2024

Abstract
Although most investigations of long-term growth trends of trees involve description of radial growth of trees, investigation of height growth of dominant and codominant trees also warrants attention for two significant reasons--the dependent variable is largely independent of stand density and it represents an index of stand productivity. Residuals from a height growth equation for jack pine (Pinus banksiana Lamb.) were used to examine long-term trends in height growth. No consistent long-term trend was apparent; however, a period of superior growth was identified during the 1960s. Short-term changes in climatic variables could account for a short duration of increased growth. As anthropogenic factors, such as air pollution, did not exhibit a trend coincident with the growth trend, they do not represent a reasonable explanation. An additional benefit of detailed examination of trends in residuals is the ability to uncover misidentification of models. The examination may suggest an inappropriate form for the equation was used, or may suggest that important variables are missing from the model. For. Sci. 44(1):158-164.
The Law of One Price in United Kingdom Soft Sawnwood Imports--A Cointegration Approach
Authors: Hänninen Riitta H. 
Published: April 2024

Abstract
The law of one price states that prices of homogenous commodities, defined in a common currency, are equal throughout the world. It implies cointegration of prices. In the present study, the law was tested for imports of soft sawnwood to the United Kingdom from Finland, Sweden, Canada, and Russia using the concept of cointegration. The data are quarterly and cover the period 1978-1992. The study used the multivariate cointegration method of Johansen instead of the bivariate method commonly used in earlier studies. The existence of the law was tested simultaneously for all four import prices and separately for pairs of prices. The results do not support the "law" but instead indicate the existence of differences over the long run between different suppliers' sawnwood prices. This suggests that imperfect competition models should be used in explaining and forecasting UK sawnwood imports. The results also raise an important issue concerning testing for competition in forest products markets, which is not usually done in connection with the modeling of markets. For. Sci. 44(1):17-23.
Modeling Timber Harvest Scheduling Problems with Multiple Criteria: An Application in Spain
Authors: Díaz-Balteiro Luis , Romero Carlos 
Published: April 2024

Abstract
This paper presents a multicriteria procedure for forest planning problems. The basic ingredients of this procedure are multigoal programming, compromise programming, and results connecting the best-compromise solutions with the concept of utility optima. The main feature of the procedure lies in the easy and transparent utility interpretation of some single best-compromise solutions even when the utility function, as is usual in a forestry context, is virtually unknown. The theoretical developments are applied to a timber harvest scheduling problem in Spain. The criteria considered are: (a) the net present value of the forest over the planning horizon, (b) the equality of harvest volume in each cutting period, (c) the area control criterion which looks for an ending regulated or even-aged forest, and (d) the ending inventory restraint. The preferential weights incorporated into the models are derived from the application of the Analytical Hierarchy Process (AHP) method to a group of experts in forestry matters. Several utility formulations are tested: (1) a separable and additive utility function linear in each criterion (i.e., a compromise solution for metric 1); (2) a Rawlsian utility function where the maximum deviation is minimized (i.e., a compromise solution for metric ∞) and (3) a family of quasi-Rawlsian utility functions. For. Sci. 44(1):47-57.
Influence of Plant Density and Soil Organic Matter on the First-Year Growth of Loblolly Pine and Sweetgum
Authors: Zutter Bruce R. , Glover Glenn R. , Mitchell Robert J. 
Published: April 2024

Abstract
Loblolly pine (Pinus taeda L.) and sweetgum (Liquidambar styraciflua L.) seedlings were planted at a range of densities on a formerly cultivated field which varied in soil organic matter (soil OM) in the upper 15 cm of the soil. Mean aboveground biomass per plant at the end of one growing season was examined to see how it varied as a function of plant density and soil OM. Biomass per plant as a function of density, holding soil OM constant, was described well by a reparameterized form of a standard yield density equation. A simple linear equation suitably described per plant biomass as a function of soil OM, holding density constant. Effects of soil OM on biomass were positive for both species, with sweetgum exhibiting a stronger response than loblolly pine. Based on the results of fitting equations to single factors, an equation considering both density and soil OM was developed and fitted using all data for each species. The equations explained 85% of the variation in response for both species. The inclusion of soil OM was more important in describing response of sweetgum than for loblolly pine. Inclusion of both density and soil OM in a single equation to describe mean response of plants in a monoculture might be extended to a mixture of species and used to examine intraspecific and interspecific competitive effects of competition and their relationship with productivity. For. Sci. 44(3):397-404.
Standard Errors of Area Estimates Obtained by Traversing and GPS
Authors: Bondesson Lennart , Ståhl Göran , Holm Sören 
Published: April 2024

Abstract
In this article, the problem of determining standard errors of area estimates obtained by traversing is addressed. In traversing, a surveyor moves along the boundary of a compartment and makes measurements at certain base points to determine their coordinates. Two cases of traversing are described: the case when coordinates are determined directly using GPS equipment and the case when distances and directions are measured from every base point to the next. It is shown that the problem of determining standard errors of the area estimates is different for the two cases. Formulas are derived from basic assumptions about the measurement errors. The efficiency of the two approaches is compared. It is found that the standard errors for the two methods often are of a similar magnitude but that the size and the shape of a compartment affect what method should be preferred. For. Sci. 44(3):405-413.
Crown Profile Modeling of Loblolly Pine by Nonparametric Regression Analysis
Authors: Doruska Paul F. , Mays James E. 
Published: April 2024

Abstract
Crown profile of loblolly pine (Pinus taeda L.) was modeled by nonparametric regression analysis. Nonparametric regression may be applicable when an underlying parametric model cannot be identified and uses only the data to fit a curve. A class of local-polynomial estimators which contains the popular kernel estimator as a special case was investigated. Kernel regression appears to fit closely to the interior data points but often possesses bias problems at the boundaries of the data, a feature less exhibited by local linear or local quadratic regression. A selection of trees was used to show that nonparametric regression captures more variation in crown shape than multiple linear regression. When using nonparametric regression, decisions must be made regarding polynomial order and bandwidth. Such decisions depend on the presence of local curvature, desired degree of smoothing, and for bandwidth in particular, the minimization of some global error criterion. In the present study, a penalized PRESS criterion (PRESS*) was selected as the global error criterion. For. Sci. 44(3):445-453.