bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil Moisture Stress Induces Transplant Shock in Stored and Unstored 2 + 0 Douglas-Fir Seedlings of Varying Root Volumes
Authors: Haase Diane L. , Rose Robin 
Published: April 2024

Abstract
Transplant shock was induced by applying a range of soil water contents to unstored and cold-stored 2-yr-old (2 + 0) bareroot Douglas-fir seedlings graded by root volume. Moisture stress had the greatest influence on morphological characteristics that express transplant shock. Seedling terminal growth, stem diameter growth, and needle length increased dramatically with increased soil moisture content. In addition, number of needles per centimeter on the terminal greatly increased with increasing moisture stress. Under high moisture stress, seedlings with relatively high root volumes tended to exhibit early reduced growth, but later showed significantly increased overall growth regardless of soil water content. In every case, seedlings grown in the driest soil had the lowest dry weights and those grown in the most moist soil had the highest weights for all seedling components. Similarly, seedlings with the smallest initial root volumes had the lowest dry weights, and those with the largest root volumes had the highest weights. The results indicate that moisture stress is a cause of transplant shock, and that increased seedling root volume may enable seedlings to avoid shock following outplanting to a specific site. FOR. SCI. 39(2):275-294.
More on Forest Regulation: An LP Perspective
Authors: Hoganson Howard M. , McDill Marc E. 
Published: April 2024

Abstract
Optimal solutions to some 2500 linear programming formulations were compared to examine the impact of forest regulation constraints. The solutions demonstrate that regulation can be expensive, with no simple rules available to describe how a regulated forest can best be achieved or what rotation age should be used for the regulated forest. The optimal rotation age can be longer or shorter than the Faustmann rotation, but results strongly suggest that the optimal rotation will be close to the Faustmann rotation if long conversion periods are used. The cost of regulation can be sensitive to the length of the conversion period, the initial age distribution of the forest, stability constraints on harvests during the conversion period, and the range of management options and rotation ages possible. Large cost savings are sometimes possible with relatively small increases in the length of the conversion period. The need to hold land idle during the conversion period can substantially increase the cost of regulation. FOR. SCI. 39(2):321-347.
Interactive Role of Elevated CO2, Nutrient Limitations, and Water Stress in the Growth Responses of Red Spruce Seedlings
Authors: Samuelson Lisa J. , Seiler John R. 
Published: April 2024

Abstract
Red spruce (Picea rubens Sarg.) seedlings were grown from seed for 5 mo in ambient (362 ppm) or elevated (711 ppm) CO2 to determine the potential effect of an increase in global CO2 concentration on seedling growth and establishment. CO2 exposure treatments were crossed with two levels of soil fertility and water stress treatments to determine if seedling dry weight, size, and fixed growth responses to elevated CO2 depended on nutrient and water supply. Seedling dry weight and size responses to elevated CO2 at 5 mo did not depend on nutrient and water supply. Seedlings grown in both soil fertility treatments and water stress treatments responded similarly to CO2 treatment. Water stress and CO2 treatments did have an interactive influence on the fixed growth potential of the terminal leader. Leaf weight, leaf area, and height of the terminal leader of water-stressed seedlings were greater in seedlings exposed to elevated CO2 during budset than seedlings exposed to ambient CO2. Total new fixed growth (lateral plus terminal) and total terminal fixed growth (leaf plus stem) were greater in seedlings that formed shoot primordia in elevated CO2 than in ambient CO2. Red spruce seedlings grown in elevated CO2 for 5 mo had greater stem diameter, height, branching density, leaf weight, root weight, stem weight, total weight, and mean relative growth rate (RGR) from 3 to 5 mo than seedlings grown in ambient CO2. Red spruce seedling responses to elevated CO2 suggest that seedling establishment in natural environments may be enhanced when ambient CO2 concentrations rise even if water and nutrient availabilities are limited. FOR. SCI. 39(2):348-358.
Interference Interactions in Simulated Pine-Hardwood Seedling Stands
Authors: Fredericksen Todd S. , Sedaker Shepard M. , Seiler John R. 
Published: April 2024

Abstract
A multiresource factor approach, using biomass allocation patterns and resource-use efficiencies, was employed to investigate interference mechanisms in mixed species tree seedling stands. Seedling mixtures of loblolly pine (Pinus taeda L.) with one of two hardwood tree species, black locust (Robinia pseudoacacia L.) or red maple (Acer rubrum L.), were grown together at close spacing under well-watered and water-stressed conditions in a greenhouse. Pure stands of each species were included as controls. Greatest biomass growth increment was observed in pure hardwood stands, while pure pine stands had the lowest increments. Interference in mixed stands was highly one-sided, with hardwoods suppressing pine growth. Mechanisms or attributes accounting for interference outcomes included higher relative growth rates, increased below-ground allocation of photosynthate, effective display of foliage, and higher resource-use efficiencies of hardwood species. Interference strategies differed for hardwood species. Black locust could be classified as an uptake specialist with a high relative growth rate and a low root:shoot ratio. Red maple was a resource-use specialist, exhibiting high internal resource-use efficiencies for light, soil moisture, and nitrogen. FOR. SCI. 39(2):383-395.
Influence of Dwarf Mistletoe and Western Spruce Budworm on Growth and Mortality of Douglas-Fir in Unmanaged Stands
Authors: Filip Gregory M. , Colbert J. J. , Shaw III C. G. , Hessburg Paul F. , Hosman Kevin P. 
Published: April 2024

Abstract
Permanent inventory plots in 94 unmanaged stands of primarily Douglas-fir (Pseudotsuga menziesii) on three national forests in Oregon and Washington were examined for growth suppression caused by dwarf mistletoe (Arceuthobium douglasii) and western spruce budworm (Choristoneura occidentalis). Ten-year increments of diameter and basal area were calculated from measurements in 1977-1987. Severity of dwarf mistletoe was scored using the six-class system. Severity and duration of defoliation were determined from aerial maps drawn over a 20-yr period.
Dwarf mistletoe significantly decreased 10-yr diameter increment. Western spruce budworm significantly reduced diameter increment and basal area increment. No significant interactions between defoliation and dwarf mistletoe were found.
Ten-year mortality of Douglas-fir due to dwarf mistletoe averaged 5% and 2% of the infected trees and basal area, respectively, for stands with moderate dwarf mistletoe severity and 4% and 3% of the infected trees and basal area, respectively, for stands with severe dwarf mistletoe infestation. Mortality was highest in stands with the most dwarf mistletoe and in stands with the most severe defoliation. There were no significant differences in diameters of dead trees among severity classes for dwarf mistletoe. Dead-tree diameters were significantly smaller in stands with the most severe defoliation during the measurement period. For. Sci. 39(3):465-477.
Ecotypic Specificity of Spruce Emergence-Stimulating Pseudomonas putida
Authors: Chanway C. P. , Holl F. B. 
Published: April 2024

Abstract
Hybrid spruce (Picea glauca X engelmannii) seed and seedlings were collected from two sites in British Columbia, near Mackenzie and near Salmon Arm. One strain of Pseudomonas putida was isolated from the rhizosphere of seedlings collected from each site. These strains were deduced to be distinct from each other based on analysis of bacterial fatty acids. Experiments were conducted to determine if P. putida affected spruce seedling emergence, and if the nature or magnitude of these effects were related to the geographic origin of bacteria and seed. Inoculation of spruce with P. putida that did not originate from the same site as the seed caused an increase in the number of seedlings that emerged, but this effect was not statistically significant. However, when the origin of the spruce seed was matched to that of the P. putida strain, a significant (P &lt; 0.05) increase in the amount and rate of seedling emergence was detected. These results are discussed in relation to the regeneration strategy of spruce in natural forests. For. Sci. 39(3):520-527.
Colonization Patterns of the Mountain Pine Beetle in Thinned and Unthinned Lodgepole Pine Stands
Authors: Preisler Haiganoush K. , Mitchell Russel G. 
Published: April 2024

Abstract
Outbreak populations of the mountain pine beetle, Dendroctonus ponderosae Hopkins, in central Oregon, were analyzed with an autologistic regression model to evaluate colonization patterns in thinned and unthinned plots of lodgepole pine, Pinus contorta Dougl. Results confirmed previous observations that beetle attacks in unmanaged stands were related to tree diameter and spacing among trees. Beetles showed a decided preference for colonizing trees with large diameters. Trees with small diameters were rarely attacked unless they were close to other trees under attack. Thinned plots were initially unattractive to beetles, but when attacks occurred, colonization was not very different from the pattern in unthinned plots. Conditional probabilities of attack for trees near other attacked trees were actually greater in thinned plots, indicating that the wide spacing between trees in these plots did not seem to interfere with the switching of attacks between trees. Vigor was not a significant covariate for estimating probability of attack in the unthinned plots. It was significant for one of the thinned plots, however, and marginally significant for another. Only one tree was colonized in a third thinned plot that had the widest spacing and the greatest vigor. A surprise was that some of the oldest trees on thinned plots appeared resistant to attack; their resistance was unrelated to diameter, vigor, or position relative to other attacked trees. For. Sci. 39(3):528-545.
Photosynthetic Apparatus in Cold-Stored Conifer Seedlings Is Affected by Nursery and Storage Photoperiod
Authors: Camm Edith L. , Lavender Denis P. 
Published: April 2024

Abstract
The photosynthetic apparatus of outdoor grown seedlings of white spruce (Picea glauca [Moench] Voss) and lodgepole pine (Pinus contorta Dougl. var. latifolia Englem.) responded in different ways to similar nursery and storage photoperiod treatments. Seedlings of both species were (1) exposed to natural or short days (SD: 8-hr photoperiod for 4 or 8 wk) during late summer, (2) returned to natural conditions, and (3) subsequently put in indoor storage at 2°C in the dark or with a low intensity photoperiod (≤15 μmol m-2-s-1, 8 hr daylength) for a 6 mo storage period starting October, December, or January. Poststorage measurements of chlorophyll (chl) a fluorescence in light-stored white spruce showed, relative to dark controls, increased variable fluorescence and decreased photochemical quenching (qP), with little increase in nonphotochemical quenching (qN). In contrast, qP was relatively unaffected in lodgepole pine seedlings, although the combination of SD treatment followed weeks later by light in storage induced an increase in qN. The sequentially applied SD treatment plus light during storage also led to the accumulation of a foliar 23kD protein in pine seedlings. The above foliar responses to the treatments were only weakly related to effects of treatments on diameter and height increase assessed 3 mo after spring planting. The interaction of the treatments shows that the pine foliage was able to integrate environmental signals received months apart. For. Sci. 39(3):546-560.
Influence of Water Relations on the Limited Expansion of Pinus Monophylla into Adjacent Cercocarpus Ledifolius Communities in the Central Great Basin
Authors: Jaindl R. G. , Doescher P. S. , Eddleman L. E. 
Published: April 2024

Abstract
We investigated the influence of plant water relations on the limited expansion and dominance of Pinus monophylla (an arid land coniferous tree) into adjacent Cercocarpus ledifolius (an evergreen nonconiferous shrub or small tree) communities. Water relations and growth of both species were monitored during 2 growing seasons on a P. monophylla dominated, alluvial fan (2070 m) and a C. ledifolius dominated, exposed ridge (2745 m). In 1990, the influence of supplemental water at the lower site was investigated. Carbon isotope composition was determined from material collected in August 1990. Predawn and midday xylem pressure potentials and transpiration rates suggested that P. monophylla was more water-use efficient than C. ledifolius. Cercocarpus ledifolius had higher transpiration rates throughout the growing season and reached lower xylem pressure potentials late in the season. This suggests C. ledifolius is better able to take advantage of available water for recharging plant moisture and rapid water use. Supplemental water's only effect was a significant increase in C. ledifolius transpiration. Carbon isotope ratios (∂13C) were more negative for C. ledifolius than P. monophylla and with increasing soil water availability. Lower rates of growth and water-use patterns by P. monophylla are not an advantage in the C. ledifolius zone and contribute to its limited expansion into this zone. For. Sci. 39(4): 629-643.
A Generalized Methodology for Estimating Forest Ingrowth at Multiple Threshold Diameters
Authors: Shifley Stephen R. , Ek Alan R. , Burk Thomas E. 
Published: April 2024

Abstract
Ingrowth is defined as the number or volume of trees that periodically grow into the smallest measured size class of a forest stand. We present a model to predict the number of ingrowth trees at a variable threshold diameter for 6 forest vegetation types common to the central United States. The model is based on observations on 2,373 remeasured inventory plots from 8 sources in Missouri, Illinois, Indiana, and Ohio. The number of ingrowth trees decreases significantly with increasing threshold diameter. The concept of crown competition factor was used to set a biologically realistic upper limit on the number of ingrowth trees for any given threshold diameter. Number of ingrowth trees · acre-1 · decade-1 was predicted as a function of the maximum possible number of ingrowth trees and the threshold diameter. Fitted models were highly significant for all forest types, and the general shape of the response surface was biologically realistic. Precision of the estimates was low because ingrowth is a highly variable process. For. Sci. 39(4):776-798.
Biotechnical Progress in Forestry: An Optimal Control Analysis
Authors: Bhattacharyya Anjana , Lyon Kenneth S. 
Published: April 2024

Abstract
A discrete time optimal control model is constructed in this paper to measure the gains from biological research expenditures in forestry. This is an extension of the timber supply model of Sedjo and Lyon (1990). We posit a production function for biotechnological improvements, which take the form of improved varieties of seeds and improved silvicultural practices. The model takes into account all the dynamic benefits from a dollar of research spending in terms of its effect on the current and future levels of technology, and of the future timber supplies resulting from the improved seeds and management practices. These separate effects are tracked in the model using state variables for the "index of technology" and for the "embodied yield index." The results of implementing the model on data for the U.S. South are reported. The empirical results indicate that biotechnical productivity gains in the range of 8 to 16% over a 25-yr period are sufficient to justify investment in biotechnology at historic levels. For. Sci. 40(1):120-141.
A Column Generation Algorithm for Solving General Forest Planning Problems with Adjacency Constraints
Authors: Weintraub Andrés , Barahona Francisco , Epstein Rafael 
Published: April 2024

Abstract
An algorithm is presented for solving general forest planning models when spatial relationships, in particular adjacent constraints, are considered. We solve a master linear program with a column generation approach. The generation of columns is done by solving a stable set problem. To preserve the adjacency properties, fractional solutions in the master problem are rounded off to integrality through a heuristic procedure. Computational experience on medium-sized problems showed that solutions with small deviations from the optimal could be obtained with moderate computational effort. For. Sci. 40(1):142-161.
Variation in Potential Volume Yield of Loblolly Pine Plantations
Authors: Hasenauer Hubert , Burkhart Harold E. , Sterba Hubert 
Published: April 2024

Abstract
Variation in the potential volume at a given site index, which is a result of differences in the maximum basal area, was investigated using data from permanent plots in loblolly pine plantations across the southern United States. The data were stratified into three physiographic regions--Atlantic Coastal Plain, Piedmont, and Gulf Coastal Plain--and the maximum stand density index (SDImax) value (Reineke 1933) was estimated for each stand by applying Sterba's (1975) extension of the competition density rule of Kira et al. (1953).
The Gulf Coastal Plain exhibited the lowest density potential and differs significantly from each of the other two regions. Between the Atlantic Coastal Plain and the Piedmont, no significant differences in the density potential exist. Significant differences mean different maximum basal areas and therefore differences in the total yield within the same site index; these differences in yield cannot be detected using the site index method only.
Data from the control plots, which represent the stand development without any thinning influences, showed that the variation between the regions was mainly due to differences in the potential of supporting trees/ha. This result was confirmed by calculating the mean relative space (Hart 1928) for each region. The relationship between top height and volume/ha for the unthinned control plots showed different volume production potential under comparable conditions at a given top height among the regions. The volume development figures follow the same order by region as the SDImax values. The highest potential (volume/ha at a given top height) is represented by the Atlantic Coastal Plain, followed by the Piedmont, followed by the Gulf Coastal Plain. For. Sci. 40(1):162-176.
Landscape Characterization of Forest Susceptibility to Gypsy Moth Defoliation
Authors: Liebhold Andrew M. , Elmes Gregory A. , Halverson Joel A. , Quimby John 
Published: April 2024

Abstract
This paper seeks to relate defoliation by the gypsy moth, Lymantria dispar (L.), to components of the landscape in order to elucidate processes operating at the regional scale. Aerial sketch maps of gypsy moth-caused defoliation in Pennsylvania from 1969-1989 were assembled in a raster-based geographical information system (GIS). These images were manipulated using Boolean algebra to determine the total defoliation frequency for each 2 X 2 km grid cell over the 21-yr study period. Because the gypsy moth became established in different parts of Pennsylvania at different times, the defoliation frequency for each cell was corrected by dividing the raw frequency by the total number of years at risk to defoliation. The number of years at risk to defoliation was calculated as the number of years each area was considered within the generally infested area minus a constant lag term, to correct for the period in years between first designation of quarantine until first defoliation. For Pennsylvania the lag was estimated as 5 yr. Average defoliation frequencies were calculated for each of six major forest type groups occurring in Pennsylvania. Pine, oak-pine, and oak-hickory type groups were the most susceptible to defoliation; maple-birch-beech, aspen-birch, and nonforest-type groups were the least susceptible. The high defoliation frequency in pine types reflects heavy feeding on oaks in these areas since gypsy moth larvae rarely feed on most pine species. Forest type group areas were further cross-tabulated by elevation classes. The three most susceptible forest type groups exhibited decreased susceptibility at elevations lower than 200 m. For. Sci. 40(1):18-29.
Sampling with Partial Replacement and Stratification
Authors: Scott Charles T. , Köhl Michael 
Published: April 2024

Abstract
Sampling with Partial Replacement (SPR) is extended to double sampling for stratification on three occasions based on the two-occasion case presented by Bickford et al. (1963). Ware and Cunia's (1962) unbiased estimator of net change is extended to double sampling for stratification on two and three occasions. A closed form solution is presented for the two-occasion case. However, the net change estimator in the second-occasion case requires solving a system of seven equations. The estimators presented make it possible to use Sampling with Partial Replacement on two or three occasions, with simple random sampling, stratified random sampling, or double sampling for stratification; and, for estimation of current attributes, their net change between occasions, and components of growth. For. Sci. 40(1):30-46.
Crown Class Transition Rates of Maturing Northern Red Oak (Quercus rubra L.)
Authors: Ward Jeffrey S. , Stephens George R. 
Published: April 2024

Abstract
Crown classes and diameters of 704 northern red oaks on medium quality sites were measured at 10-yr intervals between 1927-1987. Nominal age of northern red oaks at the beginning of the study was 25 yr. Mortality rates between ages 25-55 and between ages 55-85 decreased with each increase in crown class (i.e., mortality of dominant is &lt; codominant is &lt; intermediate is &lt; suppressed). Ascension rates into higher crown classes increased with each increase in crown class between ages 25-55 and between ages 55-85. Mortality rates of dominant, codominant, and intermediate trees were higher between ages 55-85 than between ages 25-55. The cause of the increased mortality was likely periodic episodes of defoliation which began after age 55. Within several diameter classes at age 25, survival through age 55 and the proportion found in upper canopy at age 55 increased with crown class. Mortality rates between ages 25-55 were lower for the largest northern red oak in a sprout clump than for lesser sprouts and for those trees which were not part of a sprout clump. There was no significant difference in canopy position transition rates between ages 55-85 for the largest red oaks in a sprout clump and those trees which were not part of a sprout clump. However, mortality rates between ages 55-85 of lesser trees in a sprout clump were significantly higher than for either the largest sprout in a clump or for those trees which were not part of a sprout clump. Survival of suppressed and intermediate 25-yr-old red oak was negatively related to the number of oaks in dominant and codominant crown classes. Crown class can be a powerful tool for determining the future status of maturing northern red oaks in southern New England. For. Sci. 40(2): 221-237.