bluuebunny/crossref_metadata_2025_split huggingface dataset:
Price Indexes for Deflating Public Forestry Research Expenditures
Authors: Bengston David N. 
Published: April 2024

Abstract
The extent to which inflation has eroded the real purchasing power of forestry research budgets is poorly understood. No widely accepted and satisfactory price index exists for assessing the impact of inflation on forestry research. Official government research statistics use the GNP deflator to express research expenditures in constant dollars, despite the serious shortcomings of such a broad indicator of inflation for deflating research expenditures. Two forestry research price indexes are calculated in this paper, one for USDA Forest Service research and the other for university forestry research. The GNP deflator has adequately represented the inflationary trend in Forest Service research, but it has substantially underestimated the rate of inflation in university forestry research in recent years due mainly to real growth in faculty compensation during the 1980s. The divergence between the university forestry research price index calculated in this study and the GNP deflator indicates that the purchasing power of university forestry research is significantly less than estimates based on the GNP deflator would suggest. For. Sci. 35(3):756-774.
Regression Estimators for Late-Instar Gypsy Moth Larvae at Low Population Densities
Authors: Wallner W. E. , Devito A. S. , Zarnoch S. J. 
Published: April 2024

Abstract
Two regression estimators were developed for determining densities of late-instar gypsy moth, Lymantria dispar (Lepidoptera: Lymantriidae), larvae from burlap band and pyrethrin spray counts on oak trees in Vermont, Massachusetts, Connecticut, and New York. Studies were conducted by marking larvae on individual burlap-banded trees within 15-m diameter plots and recapturing them with pyrethrin sprays to tree crowns at night. Both estimators are based on data that are relatively easy and inexpensive to gather in the field. The estimator for individual trees may be useful in determining relative densities, but the plot estimator, which had an R² of 0.99, can be used with a high degree of confidence for determining absolute densities in plots containing several oak trees. Validation of the plot density estimator at five sites in Maryland demonstrated its utility for sampling late-instar gypsy moth. Both estimators were valid only when previous years' egg-mass densities were ≤75/ha and decreased in efficiency when prior year egg masses were ≥495/ha. These estimates are best suited for density estimates in sparse or building gypsy moth populations in which other procedures are especially difficult to use or evaluate. For. Sci. 35(3):789-800.
Genetic Variance in Growth of Balsam Poplar Under 16- and 8-Hour Photosynthetic Periods
Authors: Schnekenburger Frank , Farmer Robert E. 
Published: April 2024

Abstract
Six to seven balsam poplar (Populus balsamifera L.) clones from each of four provenances on a latitudinal transect (45° to 53° at 89° to 91°W) were grown for 78 days under 16- and 8-hour photosynthetic periods. Analysis of variance and functional growth analysis were used to evaluate genetic variation in growth and development under the two regimes. Relative Growth Rate and Unit Leaf Rate of plants growing under the 8-hour regime were, respectively, 85 and 60% of those of plants under 16-hour photosynthetic periods, while final dry weight under long periods was over twice that under short ones. Leaf Area Ratio, Specific Leaf Area, and the Leaf Area Partitioning Coefficient were all larger under 8-hour periods. During the initial 30 days of the experiment, shoot-root ratio was greater under the 8-hour regime, but there was no difference between regimes by final harvest. Provenance effects were generally small and statistically nonsignificant, while clonal variation within provenances was large. The ratio of the relative growth rate of the shoot to that of roots (i.e., the allometric constant) was negatively correlated with latitude of provenance. For. Sci. 35(4):903-919.
Movement of Chloropicrin or Methylisothiocyanate through the Boles of Douglas-Fir Trees
Authors: Morrell J. J. , Newbill M. A. 
Published: April 2024

Abstract
Movement of the wood fumigants chloropicrin and methylisothiocyanate (MITC) through living Douglas-fir trees was evaluated at selected heights above treatment holes 18 and 42 months after treatment. Wood-sample extracts were analyzed by gas chromatography. After 18 months, concentrations of MITC were 10 to 30 times higher than those of chloropicrin. Concentrations of both chemicals were higher in heartwood than in the wetter sapwood. After 42 months, concentrations of both chemicals were much higher and apparent at greater distances from the point of application. MITC concentrations were again higher than those of chloropicrin, which has a lower water solubility that may limit diffusion. Both chemicals moved through Douglas-fir heartwood as far as 4 m from the application point over the 42 months. For. Sci. (36):192-195.
Soil pH and Nitrogen Influence Pisolithus Ectomycorrhizal Development and Growth of Loblolly Pine Seedlings
Authors: Marx Donald H. 
Published: April 2024

Abstract
Five families of loblolly pine were grown from April to February in fumigated soil at pH 4.8, 5.8, and 6.8. All microplots received vegetative inoculum of Pisolithus tinctorius (Pt) and three, six, or nine applications of NH4NO3 at 50 kg N/ha/application through August, which totaled 150, 300, or 450 kg N/ha. Vegetative inoculum of Pt buried in soil lost significant viability after 54 days at soil pH 6.8. Inoculum viability declined in all treatments after 81 days, but it was only a little over a third as viable at pH 6.8 as at lower pH levels. Up to three applications of NH4NO3 at 50 kg N/ha each did not affect inoculum viability.
The five test families of loblolly pine reacted similarly to soil treatments. Seedling heights, root-collar diameters, and top dry weights were more affected by soil pH than by application of N. As soil pH increased, seedling growth decreased. Dry weight of roots, total length of lateral roots, and number of short roots were not significantly influenced by either soil treatment. Total Pt ectomycorrhizal ratings (combining number of mycorrhizae and proportion of different morphological types) were about one-fourth as much at pH 6.8 as in more acid soil conditions. Applications of NH4NO3 resulting in soil concentrations of NO3-N ranging from 60 to 120 kg/ha and NH4-N ranging from 90 to 130 kg/ha at pH 4.8 and 5.8 were associated with the most abundant Pt ectomycorrhizal development. Increased N applications increased Pt development at pH 5.8 and 6.8. Calcium equivalent treatments, using CaSO4 at similar Ca concentrations, suggested seedling response was due to soil pH and not Ca concentrations. For. Sci. 36(2):224-245.
A Quantitative Description of a Deciduous Forest Canopy Using a Photographic Technique
Authors: McIntyre Blodwyn M. , Scholl Martha A. , Sigmon John T. 
Published: April 2024

Abstract
Three features of a deciduous forest canopy were measured using nondestructive techniques. Vertical distribution of leaf area was measured using an established technique (MacArthur and Horn 1969). A technique was developed and used to quantify seasonal variation in the canopy. Leaf area index (LAI) was calculated with several techniques, which were compared to litter trap LAI values to determine their accuracy. A new technique for LAI calculation was developed, which accurately estimated LAI at our site and may be applied to other eastern hardwood forests.
These three techniques are proposed to quantitatively describe a deciduous forest canopy. These measurements can be made nondestructively, with minimal equipment and labor costs, and with a high degree of accuracy. For. Sci. 36(2):381-393.
Glyphosate Translocation and Efficacy Relationships in Red Maple, Sweetgum, and Loblolly Pine Seedlings
Authors: D'Anieri Peter , Zedaker Shepard M. , Seiler John R. , Kreh Richard E. 
Published: April 2024

Abstract
Glyphosate herbicide was applied to red maple, sweetgum, and loblolly pine seedlings at the end of the second growing season to evaluate the effects of application timing and water stress on glyphosate absorption, translocation, and efficacy. Although there was no difference in 14C-glyphosate absorption among species, sweetgum translocated significantly more herbicide to the roots and stem below the treated leaf than red maple and loblolly pine. These differences may explain, in part, the variability among species in susceptibility to glyphosate. Application timing and water stress had an interacting effect on red maple and loblolly pine efficacy. Increasing water stress resulted in decreased efficacy in August, but had no consistent effect in September and October, possibly due to physiological changes associated with the development of fall dormancy. Glyphosate was most phytotoxic to sweetgum, followed by loblolly pine and red maple, which corresponds to results observed in commercial pine release applications. For. Sci. 36(2):438-447.
Monoterpene Composition and Fusiform Rust Resistance in Slash Pine
Authors: Michelozzi M. , Squillace A. E. , White T. L. 
Published: April 2024

Abstract
Cortical monoterpene composition was determined for 43 relatively resistant and 42 relatively susceptible slash pine clones selected on the basis of their fusiform rust resistance breeding values. Fifty-seven percent of the clones having high proportions of β-phellandrene were relatively resistant, while only 15% of the low β-phellandrene clones were relatively resistant. Reasons for the relationship are not clear, but presence of the high β-phellandrene gene may be linked with other traits more directly involved with resistance. Certain combinations of monoterpenes, including particular minor constituents, may be more indicative of resistance than β-phellandrene alone, but further work is needed. For the present, tree improvement workers should consider determining monoterpene composition of candidate trees prior to progeny testing, and culling trees with low β-phellandrene content. For. Sci. 36(2):470-475.
Shoot Elongation Patterns of Loblolly Pine Families Selected for Contrasting Growth Potential
Authors: Bridgwater Floyd E. 
Published: April 2024

Abstract
Ten half-sib families of loblolly pine chosen to represent a wide range of size in 8-year-old field trials, exhibited different shoot elongation patterns during their second year in retrospective seedling trials. In all but two families, the different patterns of annual shoot elongation were consistent in irrigated and nonirrigated treatments. Two families that ranked high for growth rate in the 8-year-old field trials also had greater annual shoot growth in the seedling trial without irrigation, but performed poorer than expected when well watered. The different patterns in annual height increment arose as a consequence of changes in the relative contributions of numbers of stem units, the average shoot length per stem unit, and the percentage of trees elongating. However, total annual height increment produced during the second year was a better predictor of the size of half-siblings after 8 years in field trials than any of the components of shoot growth. Families with greater size after 8 years in field trials had longer annual leaders in the seedling trial, but for varying reasons. Some were longer primarily because they had more stem units, while others had average numbers of stem units but greater-than-average stem unit lengths. The percentage of trees elongating near the end of the season was of little or no importance in determining the relative ranks of families within each of two geographic populations studied, but contributed to the differences between the two populations. For. Sci. 36(3):641-656.
The Declining Even Flow Effect and the Process of National Forest Planning
Authors: Pickens James B. , Kent Brian M. , Ashton Peter G. 
Published: April 2024

Abstract
Recent literature (McQuillan 1986) has identified what may be a serious flaw in the planning process used by the USDA Forest Service. The problem, which McQuillan called the declining even flow effect (DEFE), can occur during repeated iterations of a planning process in cases where a timber harvest scheduling model whose objective is wealth maximization subject to nondeclining yield constraints is utilized. The DEFE creates a situation in a sequence of plans over time in which the first period harvest level declines below that attained for previous planning iterations. This paper addresses the relationship between the process used by the Forest Service to develop FORPLAN models and the DEFE. An example using Kootenai National Forest planning documents is presented to illustrate the highly constrained nature of Forest Service planning models. The effect of these constraints and other characteristics of FORPLAN models on the DEFE is examined. Two items common to nearly all forest planning models, a land base which is not entirely old-growth and constraints to assure that the 40-ac clearcut limit is not violated, caused a large reduction in the DEFE observed in a FORPLAN version of McQuillan's case study model. However, one characteristic of Forest Service planning models, the use of intermediate harvest options, which plausibly could have reduced the DEFE, did not. The major conclusion of the study is that the regulations, initial conditions, and formulation of the FORPLAN model all tend to reduce the likelihood and magnitude of the DEFE. For. Sci. 36(3):665-679.
Combining Inventory Estimates with Possibly Biased Auxiliary Information
Authors: Green Edwin J. , Strawderman William E. 
Published: April 2024

Abstract
The usual method of combining sample data with auxiliary information is the familiar precision-weighted composite estimator. However, application of this estimator is straightforward only when the auxiliary information is unbiased. If this is not the case, and the bias is unaccounted for, then the risk of the usual composite estimator can be greater than that of the sample mean. We conjecture that investigators are often unsure of the possible bias in their auxiliary information. Accordingly, we develop an estimator which mimics the usual composite estimator when the auxiliary information is unbiased, yet dominates the sample mean even as the bias becomes large. In addition, unlike the usual composite estimator, the new estimator does not require one to specify the variance of the auxiliary information. The performance of both estimators, and the sample mean, is examined based on results of a simulation trial on actual sample data. For. Sci 36(3):693-704.
Sprouting Shrub Response to Different Seasons and Fuel Consumption Levels of Prescribed Fire in Sierra Nevada Mixed Conifer Ecosystems
Authors: Kauffman J. B. , Martin R. E. 
Published: April 2024

Abstract
Virtually all shrub species present in mixed conifer forests of the Sierra Nevada have evolved specialized adaptations to survive the frequent low intensity surface fires that characterized the fire regime of this ecosystem. In this study we examined the variable sprouting response of broad-leaved shrubs and hardwoods following prescribed fires burned under a wide range of environmental and fuel conditions. Shrub survival was often dramatically different between treatments (i.e., fuel consumption level and season of burn), species, and size classes within plant species. Of the four different burn treatments, survival of the shrubs and hardwoods was as low as 12% after early fall burns (high levels of fuel consumption) and as high as 79% after early spring burn treatments (moderate levels of fuel consumption). As much as 95% of the smallest size of the small classes of shrubs (i.e., those ≤50 g dry weight biomass) were killed by prescribed fires. In contrast, the majority of larger individuals survived fires of low-moderate consumption, but rates of survival declined with increasing levels of fuel consumption.
Post-fire shrub physiognomy was significantly lower in crown volume, crown area, height, and aboveground biomass. The number of individual shrub stems per individual significantly increased after fire. Postfire biomass partitioning was different among sprouting species; in the deciduous-leaved Quercus kelloggii, the percentage of aboveground biomass composed of leaves was lower, and the percentage composed of woody tissues was higher than that of the evergreen-leaved Lithocarpus densiflorus. For. Sci. 36(3):748-764.
Critical Height Versus Importance Sampling for Log Volume: Does Critical Height Prevail?
Authors: Deusen Paul C. Van 
Published: April 2024

Abstract
The estimator developed in Van Deusen (1987) is generalized to allow for unbiased estimation of log or tree volume using the critical height method. Comparisons are made with importance sampling (Gregoire et al. 1986) that suggest that the critical height method is more efficient and robust. The critical height method also requires fewer computations in the field. For. Sci. 36(4):930-938.
Individual Choice and Regional Acreage Response to Cost-Sharing in the South, 1971-1981
Authors: Hardie Ian W. , Parks Peter J. 
Published: April 2024

Abstract
Total acreage responding to a given economic incentive is a key measure of the effectiveness of many government forest land-use programs. Examples are the FIP and America the Beautiful programs. Acreage response depends both on landowner behavior and on land characteristics. Prediction of this response for new or untried government incentives consequently requires simultaneous estimation of landowner land-use decisions and of the number of acres affected by the decisions. A method to predict aggregate acreage response to proposed land-use programs is described in the paper. This method is illustrated by an analysis of how cost-sharing could have affected NIPF owner investment in pine regeneration on harvested lands in the South in 1971-1981. Results show that cost-sharing may have encouraged 70% of the regeneration investment observed during the period, and that changes in the cost-share incentive would have been an effective way to change the amount of pine acreage planted or seeded in the South during this period. Application of the method to proposed future programs would require a new area frame sample survey. For. Sci. 37(1):175-190.
Principal Components Regression to Mitigate the Effects of Multicollinearity
Authors: Morzuch Bernard J. , Ruark Gregory A. 
Published: April 2024

Abstract
One consequence of multicollinearity among the structural independent variables of a regression model is that variables are frequently deleted as a means of proceeding with sensible hypothesis tests. Principal components regression has the advantage of avoiding model specification error due to variable deletion. The technique works as follows: the independent variables are orthogonalized into their principal components; components with low information content are deleted; the model is estimated by ordinary least squares; then the principal component estimators are converted into coefficients in the original parameter space, where a judgement about their contribution is made via an F-test. An example using tree growth data is presented to demonstrate the merits of principal components regression over variable deletion. Results indicate that "correct" structural specification does not have to be compromised through variable deletion when collinearity is present. This obviously has implications for large-scaled regression models, in which an increased number of independent variables in the specification may promote a level of collinearity that is not conducive to making statistical inferences. Analytical methods like principal components, that adjust for the effects of collinearity on the variable selection process, are merited. For. Sci. 37(1):191-199.
Distributive Effects of Forest Service Attempts to Maintain Community Stability
Authors: Daniels Steven E. , Hyde William F. , Wear David N. 
Published: April 2024

Abstract
Community stability is an objective of USDA Forest Service timber sales. This paper examines that objective, and the success the Forest Service can have in attaining it, through its intended maintenance of a constant volume timber harvest schedule. We apply a three-factor, two-sector modified general equilibrium model with empirical evidence from the timber-based counties of western Montana. Departure from a market responsive timber policy can have positive impacts on the wood products sector, but the net effects on the local community are very small. The costs to the public treasury of pursuing such a policy dwarf these small community benefits. For. Sci. 37(1):245-260.
Nitrogen and Family Effects on Biomass Allocation of Loblolly Pine Seedlings
Authors: Li Bailian , Allen H. L. , McKeand S. E. 
Published: April 2024

Abstract
Biomass of stem, needles, and roots were determined for seedlings of 23 open-pollinated loblolly pine families alter 20 weeks' growth in a greenhouse under two nitrogen (N) levels (5 and 50 ppm). Allometric analysis was used to determine the N and family effects on the biomass allocation. Nitrogen had significant effects on seedling growth and biomass allocation to stem, needles, and roots. Low N resulted in smaller seedling size, but relatively more biomass was allocated to roots than under the high N condition. N stress generally favored biomass allocation to roots at the expense of needles or both needles and stem. Relative allocation of biomass to roots was significantly different among families with low N but not with high N. Larger seedlings exhibited greater allocation to roots possibly as a result of greater N stress. Different patterns of biomass allocation among loblolly pine families were related to their stem weight and height. Families with superior stem weight and height in both N environments had the largest root biomass proportional to seedling size in low N and had the smallest under the high N treatment. For. Sci. 37(1):271-283.
Relationship Between Total Nonstructural Carbohydrate Concentration and Root Diameter in Sugar Maple
Authors: Kolb T. E. , McCormick L. H. 
Published: April 2024

Abstract
Total nonstructural carbohydrate (TNC) concentration, an estimate of the carbohydrate energy readily available to the plant, was measured by chemical extraction (enzymatic hydrolysis) in dormant season roots of sugar maple (Acer saccharum Marsh.). In all sample trees, TNC concentration increased as root diameter decreased. On the average, root diameter explained 60% of the variation in TNC concentration within an individual tree. Linear regressions of TNC concentration on root diameter did not differ significantly among trees. Bias on TNC concentration introduced by differences in root size can be minimized by sampling similar root diameter classes among trees, or by adjusting TNC concentration to a common root size. For. Sci. 37(1):343-346.
Factors Affecting Nitrogen Concentration of Fine Roots in Forest Communities: Regression Analysis of Literature Data
Authors: Yin Xiwei , Perry James A. 
Published: April 2024

Abstract
Literature data on nitrogen concentration of live fine roots (≤10 mm in diameter) in forest communities were analyzed by multiple linear regression. After appropriate transformations, root diameter, minimum monthly mean temperature, forest origin, and forest type together accounted for 93.2% of variation in N concentration. We suggest the following possible ecological bases: fine-root N concentration (1) was negatively related to root diameter because of increased percent old tissue and structural material with root size, (2) was negatively related to minimum monthly mean temperature because of a combined effect of soil available N, root absorption capacity, and carbon production, and/or because of selection pressure of cold winter on the genetic trait of higher N in fine roots, (3) was higher in plantations than in natural stands because of species and site selections and management history, and (4) was higher in broad-leaved than needle-leaved forests because of different N cycling rates. For. Sci. 37(1):374-382.