bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seed Source Variation in Specific Gravity of Loblolly Pine Grown in a Common Environment in Arkansas
Authors: Tauer C. G. , Loo-Dinkins Judy A. 
Published: April 2024

Abstract
Wood specific gravity in a rangewide sample of loblolly pine (Pinus taeda L.) grown in a common environment in southwest Arkansas differed from reported values of trees sampled in situ. Differences were greatest at the extremes of the species range. In the common environment trees from western and northeastern sources produced the highest specific gravities; northeastern trees produced the highest dry weight per hectare yields but they were not significantly greater than yields of trees from east coast and northwest sources. On an individual tree basis, specific gravity was significantly negatively correlated with height, diameter, and volume, although the r values were small; 0.272, 0.090, and 0.129, respectively. Provenance region correlations between specific gravity and growth and stand density parameters were generally weak to negligible. For. Sci. 36(4):1133-1145.
Storage Temperature and Duration Influence Cold Tolerance of Red Spruce Foliage
Authors: DeHayes D. H. , Waite C. E. , Ingle M. A. 
Published: April 2024

Abstract
Laboratory assessments of cold tolerance were conducted to examine the influence of duration and temperature of foliar sample storage on relative and absolute cold tolerance of excised shoots of red spruce (Picea rubens Sarg.) trees during midwinter and early spring. Although differences in cold tolerance associated with temperature and duration of sample storage were statistically significant, the rate of dehardening of red spruce foliar samples was largely a function of the storage temperature/duration combination rather than either temperature or duration alone. Foliar samples stored at 15°C dehardened significantly after 45 hours of storage, whereas samples stored at 24°C dehardened significantly after only 18 hours. Samples stored at 4°C for up to 72 hours were similar in cold tolerance to fresh samples. Foliar samples from different trees responded differentially to foliar sample storage regimes, indicating that both absolute and relative cold tolerance of individual trees may be altered by relatively short periods of sample storage at above-freezing temperatures. For. Sci. 36(4):1153-1158.
Predicting Post-Harvest Performance of Advance Red Oak Reproduction in the Southern Appalachians
Authors: Loftis David L. 
Published: April 2024

Abstract
Models are presented for predicting: (1) height growth of red oak advance reproduction after clearcutting, and (2) the probability of stems becoming dominants or codominants in new stands as a function of preharvest size of advance reproduction and site quality. The second model permits silviculturists to predict, prior to harvest, the contribution to a new stand of an existing population of advance red oak reproduction. For. Sci. 36(4):908-916.
Intensification of Dwarf Mistletoe on Southwestern Douglas-fir
Authors: Geils B. W. , Mathiasen R. L. 
Published: April 2024

Abstract
From a sample of 445 Douglas-fir trees infected with dwarf mistletoe (Arceuthobium douglasii), three models for predicting mistletoe intensification are developed. Two models relate the mean rate of intensification since the tree became infected to initial and current tree conditions; the third one describes the proportion of trees that increased by 0, 1, 2, or more classes of dwarf mistletoe infection (DMR) in the past 10 years. The models suggest that the rate of intensification is most rapid (2 DMR classes per decade) for severely infected trees of small diameter and slowest (0.5 DMR classes per decade) for lightly infected trees of large diameter. Intensification within a tree increases with the abundance of mistletoe in nearby, larger trees and with stand basal area. No other significant relations were found between rates of intensification and site or stand factors such as habitat type, site productivity, or stand composition. A comparison of mistletoe ratings for standing trees and ratings for carefully examined felled trees indicates that trees can be correctly rated by standard procedures about 75% of the time. For. Sci. 36(4):955-969.
Ecophysiological Responses in Mesic versus Xeric Hardwood Species to an Early-Season Drought in Central Pennsylvania
Authors: Abrams Marc D. , Schultz Jack C. , Kleiner Karl W. 
Published: April 2024

Abstract
Field and laboratory studies were used to evaluate net photosynthesis and plant and tissue water relations in saplings of co-occurring xeric (Quercus prinus and Q. ilicifolia) versus mesic (Q. rubra and Castanea dentata) hardwood species during a droughty summer. Mean daily net photosynthesis, leaf conductance, leaf water potential, and water use efficiency were reduced in all four species during the peak drought period. Throughout the study, net photosynthesis and leaf conductance were on average high in Q. ilicifolia and Q. prinus, intermediate in Q. rubra, and low in C. dentata. Leaf water potential was generally highest in C. dentata and not significantly different among the Quercus species. There were few consistent patterns in the tissue water relations data, including a lack of osmotic adjustment during peak drought, a lack of correlation between osmotic potentials and gas exchange rates, decreases in osmotic potentials and tissue elasticity after the peak drought period ended, and bulk leaf water potential values below the osmotic potential at zero turgor, despite relatively high gas exchange in those plants. Thus, the tissue water relations data provided little insight to mechanisms of drought tolerance in these species and suggest some methodology problems using standard pressure-volume procedures. For. Sci. 36(4):970-981.
Effects of Time and Frequency of Cutting on Hardwood Root Reserves and Sprout Growth
Authors: Kays Jonathan S. , Canham Charles D. 
Published: April 2024

Abstract
We examined the effects of time and frequency of cutting during the growing season on fall root starch reserves and sprout production in saplings of four hardwood tree species--red maple, gray birch, white ash, and black cherry. For all species, there was a well-defined window of time during the growing season when cutting resulted in low levels of starch in roots at the end of the growing season, and subsequent low sprout growth rates the following year. Cutting at the very beginning or the very end of the growing season resulted in the highest levels of fall root reserves and sprout production. The duration of the window varied for each species and was closely related to the phenology of aboveground growth. The species with a determinant shoot growth pattern had the shortest window (white ash), while the two species with the most indeterminant shoot growth pattern had the longest windows (red maple, gray birch). For. Sci. 37(2):524-539.
Integration of Geographic Information Systems with a Diagnostic Wind Field Model for Fire Management
Authors: Zack James A. , Minnich Richard A. 
Published: April 2024

Abstract
The past 10 years have seen an increased interest in diagnostic wind modeling efforts in the fields of air pollution research and wind energy engineering. Applications relating wind to forest fire behavior are also beginning to capitalize on computer-generated outputs from wind models. Most wind model outputs have been considered useful only as intermediate data files loaded into specialized software packages for further processing. Output data are used to generate various output products without being passed into sophisticated mathematical models. With the developed technology of geographic information systems (GIS), new map products can be created. If designed properly, these maps can pass information more efficiently to both the decision maker and the GIS for further analysis. The methods used to create and edit topographic and meteorological databases, display the results of the KRISSY diagnostic wind field model, and perform analyses on the topography and estimated wind field are described. For. Sci. 37(2):560-573.
Changing Stand Structure and Regional Growth Reductions in Georgia's Natural Pine Stands
Authors: Bechtold W. A. , Ruark G. A. , Lloyd F. T. 
Published: April 2024

Abstract
Forest Inventory and Analysis (FIA) data indicate reductions in the growth of naturally regenerated pines in Georgia between the two latest measurement periods (1961-72 vs. 1972-82). Analysis of Covariance was used to adjust stand-level basal area growth rates for differences between periods in stand age, stand density, site index, mortality, and hardwood competition. The adjusted mean growth of pines during the later period declined by 19% for natural loblolly, 28% for natural shortleaf, and 28% for natural slash pine stands. The factor(s) causing the reductions remain unidentified, but differences in stand structure are not likely responsible. For. Sci. 37(2):703-717.
Fine Root Carbohydrate Dynamics of Loblolly Pine Seedlings Grown Under Contrasting Levels of Soil Moisture
Authors: Hallgren Stephen W. , Tauer Charles G. , Lock John E. 
Published: April 2024

Abstract
Fine root growth, mortality, and carbohydrate concentration were compared for North Carolina and Oklahoma-Arkansas families of loblolly pine (Pinus taeda L.) seedlings under well-watered and drought conditions. The objective was to determine if moisture stress affected fine root carbohydrate dynamics and fine root longevity. Seedlings under drought produced new roots with the same starch concentration as well-watered seedlings, despite a 50% reduction in whole-plant growth. The starch concentration in fine roots of seedlings grown under periodic drought did not increase with age; in contrast, the starch concentration in fine roots of well-watered seedlings continued to increase for at least 70 days. There was no evidence that moisture stress accelerated fine root starch depletion. Fine root starch concentration was around 20% less and sugar concentration nearly 13% greater under periodic drought than under well-watered conditions. Fine root starch concentration never dropped below 4%. Fine root mortality was negligible and showed no effect of treatment or seed source. The results of this study do not support the hypothesis that drought accelerates carbohydrate depletion and thereby increases fine root mortality. Plants from the Oklahoma-Arkansas families contained higher starch concentrations in roots and shoots than plants from North Carolina families but produced slightly less biomass. For. Sci. 37(3):766-780.
Strategic Positioning in a Turbulent Environment: An Empirical Study of Determinants of Performance in the North American Forest Industry
Authors: Booth Darcie , Vertinsky Ilan 
Published: April 2024

Abstract
This paper investigates the extent to which geographical and product diversification provide firms in the forest products industry of North America with means for coping with a turbulent environment. A turbulent environment is one where there is a high degree of uncertainty and sharp discontinuities; hence it is an unpredictable environment. The relationship between the firm's strategic positioning and performance is investigated. Six models relating various attributes of performance, including measures of risk, returns, and growth, to strategic positioning and other attributes of firms were estimated using regression equations. The results indicate that unrelated-product diversification and geographical diversification reduce risk, but at a significant cost in terms of performance, notably rate of return. Opportunities for related-product diversification that reduce risk are limited. Product differentiation and investment in new technology provide opportunities for increased returns and risk reduction. For. Sci. 37(3):903-923.
Seasonal Cambial Activity in Larix laricina Saplings in Relation to Endogenous Indol-3-ylacetic Acid, Sucrose, and Coniferin
Authors: Savidge Rodney A. 
Published: April 2024

Abstract
Although some quantitative research on the role of endogenous auxin (indol-3-ylacetic acid, IAA) in regulating anatomical aspects of diameter growth in trees has been reported, there have been no attempts to correlate cambial IAA content with biochemical aspects of wood formation. In this study, the cambial region (phloem, cambial zone, and differentiating cambial derivatives when present) at four positions (1, 3, 8, and 17 years) in the main stems of 20-year-old Larix laricina (Du Roi) K. Koch were sampled to determine the endogenous contents of IAA, sucrose and coniferin in relation to seasonal cambial growth. IAA and sucrose were both present throughout the dormant period, and their concentrations increased in late spring and summer in association with leaf and shoot development. Coniferin, the principal molecule supporting lignification in conifers, was not detected throughout the winter period of cambial dormancy, but was detected in spring immediately preceding resumption of cambial cell division, was present throughout the period of cambial growth, but then disappeared after the last-produced latewood tracheids had completed their differentiation. The coniferin content varied independently of IAA and sucrose, suggesting that the cambium's seasonal competence for coniferin biosynthesis is controlled by factors other than IAA or sucrose availability. For. Sci. 37(3):953-958.
Needlefall, Canopy Light Interception, and Productivity of Young Intensively Managed Slash and Loblolly Pine Stands
Authors: Dalla-Tea F. , Jokela E. J. 
Published: April 2024

Abstract
Canopy dynamics, light interception, and productivity of 6-yr-old slash (Pinus elliottii vat. elliottii Engelm.) and loblolly pine (P. taeda L.) were investigated using a 2 x 2 x 2 factorial experiment (species, annual fertilization, sustained weed control) in north central Florida. The strong nutritional gradient imposed by the cultural treatments significantly accelerated canopy development. Needlefall (NF) mass for the weed control + fertilization treatments was increased over the checks by about 400% (0.8 to 4.0 Mg ha-1) for slash pine and 1050% (from 0.4 to 4.6 Mg ha-1) for loblolly pine. Levels of annual NF were strongly correlated (r² &gt; 0.90) with stand basal area, and cumulative NF through time was successfully modeled using a logistic function. Cultural treatments had no significant effect on needle longevity or temporal NF patterns; however, large treatment related responses in leaf area index (LAI; all-sided) were apparent for both species (slash pine = 1.5 to 7.2 m² m-2 loblolly pine = 1.0 to 10.6 m² m-2). Mean annual light interception (photosynthetically active radiation) for the check and combination treatments paralleled LAI responses and ranged from 28 to 74% for slash pine and 22 to 81% for loblolly pine. Significant species differences in aboveground biomass production (loblolly pine = 3.1 to 16.0 Mg ha-1 yr-1; slash pine = 3.5 to 8.0 Mg ha-1 yr-1) were principally due to greater LAI (reflecting differences in specific leaf area and branch structure) and higher light use efficiency (0.81 vs. 0.47 g MJ-1) of loblolly pine. For. Sci. 37(5):1298-1313.
Predicting the Effects of Silvicultural Regime on Branch Size and Crown Wood Core in Douglas-Fir
Authors: Maguire Douglas A. , Kershaw John A. , Hann David W. 
Published: April 2024

Abstract
Three major determinants of wood quality in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) were estimated from the dynamics of crown structure in ORGANON, an individual-tree, distance-independent growth model. Branch whorl locations were estimated directly from the height growth predictions assuming formation of one whorl per year. Mean maximum branch diameter was predicted as crown base receded past each whorl; branch diameter estimates were based on current depth of the whorl into crown, tree diameter, stand relative density, and site index. Diameter of crown wood core was established as diameter inside bark, likewise at time of crown recession past each branch whorl. This approach facilitated description of harvested log distribution (40-ft butt logs) by various branch size, whorl frequency, and crown wood core indices. Based on projections of a 9-yr-old Douglas-fir stand to final harvest at 65 years, thinning precommercially to 121 trees/ac at age 9 resulted in a BD4 (mean of four largest branch diameters per log) of 2.5 in., vs. 1.5 in. for the unthinned stand (484 trees/ac). When thinned to 121 trees/ac, approximately 55% of the volume/ac in 40-ft butt logs consisted of crown wood as opposed to 30% at 484 trees/ac. Responses to subsequent thinnings were less pronounced, but included larger branches in the largest 80 trees/ac, and larger total crown wood percentages for a given initial stand density. Thinning from below resulted in larger average BD4's and slightly greater crown wood percentages than proportional thinning. Individual-tree growth models that contain a crown recession component can easily be modified to predict crown wood core and indices of branch size. For. Sci. 37(5):1409-1428.
Effects of Southwestern Pine Tip Moth and Vegetation Competition on Ponderosa Pine Growth
Authors: Long David W. , Wagner Michael R. 
Published: April 2024

Abstract
The effects of southwestern pine tip moth Rhyacionia neomexicana (Dyar) and vegetation competition on ponderosa pine Pinus ponderosa (Doug. ex Laws) growth was studied in northern Arizona. Tip moth attack rates varied significantly among three sites. Weeding had little effect on attack rates but increased tree survival by 17%, height growth by 96%, and diameter growth by 83%. Insectidde treatment for tip moth control increased height growth 49% and diameter growth only 12%. High tree mortality rates in insecticide treated plots suggest a possible phytotoxic effect of the insecticide. Tree growth declined as tip moth attacks increased. Height growth was further reduced with each added year of tip moth attack. Diameter growth was less affected by multiple years of attack. For. Sci. 38(1):173-186.
Solving for Habitat Connections as a Steiner Network Problem
Authors: Sessions John 
Published: April 2024

Abstract
The problem of finding habitat connections in forest planning can be modeled as a Steiner network problem. Although exact solutions exist for solving Steiner network problems, no methods that can be solved in polynomial time are known. A network modeling procedure for habitat connections is discussed and a heuristic algorithm is presented which is suitable for solving large scale Steiner networks. For. Sci. 38(1):203-207.
Thinning and Nitrogen Fertilization in a Grand Fir Stand Infested with Western Spruce Budworm. Part III: Tree Wound Dynamics
Authors: Filip Gregory M. , Wickman Boyd E. , Mason Richard R. , Parks Catherine A. , Hosman Kevin P. 
Published: April 2024

Abstract
In a grand fir stand defoliated by western spruce budworm, we tested the effects of thinning and urea fertilization on stem-wound closure and associated wood decay as affected by tree growth and vigor. After 3 years, thinning or fertilizing significantly improved tree diameter growth, and fertilizing significantly improved tree vigor as measured by cambial electrical resistance (CER). Although wound closure and cross-sectional area of decay were not significantly affected by our treatments, the percentage of stem cross-sectional area with decay was significantly less in trees that had been both thinned and fertilized. We found relatively poor correlations between decay area or decay percent and tree vigor, tree diameter growth, or wound diameter, but relatively moderate correlations between wound diameter and tree vigor or tree growth. Heterobasidion annosum was the dominant fungus causing the stem decay. Our results support the use of thinning and fertilization to improve grand fir growth and vigor and reduce losses from wound-associated stem decay. For. Sci. 38(2):265-274.
Thinning and Nitrogen Fertilization in a Grand Fir Stand Infested with Western Spruce Budworm. Part IV: An Ecosystem Management Perspective
Authors: Waring R. H. , Savage T. , Cromack K. , Rose C. 
Published: April 2024

Abstract
A stand of grand fir, Abies grandis (Dougl.) Lindl., was thinned and (or) fertilized with 350 kg/ha of nitrogen during an outbreak of the western spruce budworm, Choristoneura occidentalis Freeman. With thinning, the leaf area index was reduced by &gt;30%. Tree growth efficiency, measured as wood production per unit of leaf area, increased by 60% within 2 years. Thinning combined with fertilization improved growth efficiency by 140%. Fertilization without thinning brought a much delayed response in growth, awaiting some beneficial effects of defoliation.
Fertilization provided tree roots in the upper soil horizons access to nitrogen during the spring, increasing the concentration of nitrogen in emerging foliage from 1 to 1.5% of dry weight and free amino adds levels 4-fold. Foliage enriched in amino acids increased shoot growth 3-fold, more than compensating for any nutritional benefits to insect larvae.
From an ecosystem perspective, managers should recognize that allowing pine forests to be replaced with fir through fire protection and selective logging has increased the nitrogen demand beyond that readily supplied in the ponderosa pine/true fir type. Fertilizing with one application of nitrogen at the time of an insect outbreak may reduce mortality and associated fire hazard through a period of up to 5 years. For. Sci. 38(2):275-286.
Production and Nutrient Cycling in Mixed Plantations of Eucalyptus and Albizia in Hawaii
Authors: Binkley Dan , Dunkin Kristie A. , DeBell Dean , Ryan Michael G. 
Published: April 2024

Abstract
Experimental plantations of pure Eucalyptus saligna (Sm.), pure Albizia falcataria (L.) Fosberg (a nitrogen-fixing species), and five proportions of mixtures of these species were examined at age 6 for biomass, production, nutrient cycling in litterfall, and resource-use efficiencies. Biomass was greatest in the 34% Eucalyptus/66% Albizia treatment, averaging 174 Mg/ha, compared with 148 Mg/ha in the fertilized pure Eucalyptus treatment and 132 Mg/ha for the pure Albizia treatment. The 34% Eucalyptus/66% Albizia treatment also showed the greatest aboveground net primary production (52 Mg ha-1 yr-1) and annual increment (39 Mg ha-1 yr-1). The N and P content of above-ground litterfall ranged from 35 and 3.5 kg ha-1 yr-1 in pure Eucalyptus to 240 and 9.5 kg ha-1 yr-1 in pure Albizia. Nutrient-use efficiency, defined as Mg of ANPP/kg of nutrient in fine litterfall, was greater for Eucalyptus (1.1 for N, 13.4 for P) than for Albizia (0.2 for N, 5.7 for P). Light-use efficiency ranged from about 14 kJ/MJ of intercepted light in the pure Albizia treatment, to 17 kJ/MJ in the pure Eucalyptus treatment, to 18 in the 34% Eucalyptus/66% Albizia treatment. The patterns of productivity across the mixtures resulted from the combination of (1) greater nutrient use efficiency of Eucalyptus, (2) greater nutrient cycling under Albizia, and (3) greater light capture and high use efficiency in mixed stands. For. Sci. 38(2):393-408.