bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of Laminated Root Rot on Relationships Between Stem Growth and Root-System Size, Morphology, and Spatial Distribution in Douglas-fir
Authors: Bloomberg W. J. , Hall A. A. 
Published: April 2024

Abstract
Root-system size (length, cross-sectional area, and volume) was measured in 30- to 40-year-old Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) in five stands. Mean root-system size varied widely among stands (length 2,485-5,316 cm; cross-sectional area 4,070-13,520 cm²; volume 72,760-251,020 cm³). Percentage of roots decayed by Phellinus weirii varied among stands and among root orders ranging 22-83 percent by length and 21-84 percent by volume. Root size distribution in P. weirii-infected trees was generally of the same magnitude and pattern as in healthy trees. Diameter at breast height (dbh) was highly correlated with total root-system size in all stands in all three root measures. Height was highly correlated with total root-system size in four stands. Diameter at breast height increment and dbh increment percent and height-dbh ratio were moderately correlated with root-system size in some stands and for some root measures. Height increment percent was poorly correlated with root-system size. Correlations of most stem variables with sizes or percent decay of roots stratified by root orders and by distance and depth zones were significantly stronger than correlations with total root-system size. Healthy and infected trees differed in the root orders and zones that were most strongly correlated with stem-growth variables. Diameter at breast height and height were mostly positively correlated with infected and healthy root sizes whereas increment variables were predominantly inversely correlated with infected root size. Stem radii measured vertically above junctions of infected roots with the stem base were smaller than those measured above junctions of healthy roots. Radial increments above infected roots producing adventitious branches were greater than those above other infected roots or above healthy roots. Forest Sci. 32:202-219.
Response of Three Conifer Species to Site Preparation and Shrub Control
Authors: Lanini W. T. , Radosevich S. R. 
Published: April 2024

Abstract
A 5-year field study was conducted to determine the effect of three methods of site preparation in combination with three levels of shrub suppression on subsequent microenvironmental, shrub and tree responses. Shrub canopy volume and survival, growth, and water potential of planted ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Lawson.), sugar pine [Pinus lambertiana Dougl. (Strobus L. Mold.)], and white fir [Abies concolor (Gord. & Glend.) Lindl.] were measured. Ponderosa pine survived better than sugar pine or white fir regardless of shrub presence or absence. Shrub canopy volume did not influence tree survival; however, the presence of shrub debris from some treatments increased planting difficulty and resulted in increased tree mortality. Predawn and midday water potential, height, stem diameter, and canopy volume of conifers were highest when shrub canopy volumes were low. Forest Sci. 32:61-77.
Adaptive Variation in Pinus ponderosa from Intermountain Regions. I Snake and Salmon River Basins
Authors: Rehfeldt G. E. 
Published: April 2024

Abstract
Genetic differentiation of 64 populations from central Idaho was studied in field, greenhouse, and laboratory tests. Analyses of variables reflecting growth potential, phenology, morphology, cold hardiness, and periodicity of shoot elongation revealed population differentiation for a variety of traits. Regression models related as much as 61 percent of the variance among populations to the elevation and geographic location of the seed source. Clinal patterns of adaptive variation provide the basis for developing seed transfer guidelines that will control maladaptation in reforestation. In central Idaho, for example, seed transfer should be limited to within 180 m of the seed source. Forest Sci. 32:79-92.
FORCAT: A Single Tree Model of Stand Development Following Clearcutting on the Cumberland Plateau
Authors: Waldrop T. A. , Buckner E. R. , Shugart H. H. , McGee C. E. 
Published: April 2024

Abstract
A single tree model, FORCAT, was developed as a forest management tool for the Cumberland Plateau region of East Tennessee. FORET (Shugart and West 1977), a gap model of forest succession in East Tennessee, served as the basic program for the simulation of stand regeneration, competition, tree growth, and mortality. Gap models have been used to simulate successional changes in species composition over periods of up to 1,000 years for many different forest types. Even though the output of gap models has included specific information such as basal area and density, the accuracy of short-term predictions of these variables remains relatively untested for forest management purposes. A test of FORET indicated that the model was not readily adaptable to different sites and management schemes. Therefore, major modifications to the basic program were necessary. Some of the more significant changes included in FORCAT are: (1) beginning the simulation with a mature stand (which was immediately clearcut) rather than bare ground, (2) growth rates based on site quality and local climatic conditions, (3) basing seed availability on species-specific characteristics, and (4) simulation of periodic clearcutting and prescribed burning.
Validation tests showed that FORCAT successfully predicted basal area, numbers of trees, and species composition of 50- to 100-year-old stands. In younger stands, however, the number of seedlings of pioneer species was underestimated. This variance emphasizes the difficulty of projecting regeneration abundance and indicates the need for further model refinement. Nevertheless, FORCAT serves as a bridge from a highly theoretical model of forest succession to a useful forest management tool. Additional inputs controlling seed availability are needed to make FORCAT more broadly applicable to all forest types found on the Cumberland Plateau. Forest Sci. 32: 297-317.
Environmental and Historical Factors Affecting Red and White Fir Regeneration in Ecotonal Forests
Authors: Parker Albert J. 
Published: April 2024

Abstract
Diameter-class distributions of thirty mixed red fir/white fir forests from Yosemite National Park, California, are used to examine patterns of canopy dominance and regeneration modes of these two zonal dominants. Successful regeneration of each species is associated with open canopies and nutrient rich substrates. Red fir regenerates in greater numbers on a wider range of sites, but suffers greater mortality than white fir. Patterns of canopy dominance indicate that white fir tolerates canopy closure and dominates on nutrient-rich sites in montane forests, whereas red fir is less tolerant of shading and dominates on disturbed, nutrient-poor substrates in subalpine forests. These patterns are interpreted as adaptive responses to complex interactions of site factors, disturbance frequency, and biotic constraints along an elevational gradient. Forest Sci. 32:339-347.
Time-Series Analyses of Tree-Ring Chronologies
Authors: Monserud Robert A. 
Published: April 2024

Abstract
The stochastic time-dependent structure of 33 tree-ring series from the dendrochronology literature was analyzed using autoregressive moving average (ARMA) models. Significant autocorrelation was found in every tree-ring series, for not one of the series was white noise. The overall best model was the mixed ARMA(1,1) process. The collection of parameter estimates for this mixed model were tightly clustered, even though the data were collected from the entire length of western North America. High-order autoregressive models (P = 2 to 4) were always a good choice, but usually not as good as the mixed ARMA(1,1) model. Rarely did the first-order autoregressive model provide an adequate description of the data. Standardization (i.e., weighted residuals from the growth trend) of ring-width series into ring-index series was a useful--and often necessary--step for producing a stationary time series. Many of the unstandardized ring-width series demonstrated a strong tendency toward nonstationarity. The practice of removing certain frequencies by passing the data through a running average filter was found to introduce spurious correlations that did not exist in the original data, and thereby obfuscated any statistical analysis in the time domain. The cross correlation function was found to be a useful tool both for examining the association between series and for synchronizing series, especially after prewhitening with appropriate ARMA models. Because significant autocorrelation was found in every series examined, it is recommended that all statistical analyses be performed using the prewhitened residuals from an appropriate ARMA model. Forest Sci. 32:349-372.
A Dynamic Forest Sector Model with a Swedish Case
Authors: Lönnstedt Lars 
Published: April 2024

Abstract
Forest management and new plant investments are long-term decisions. Consequently, strategic planning is vital for the companies involved and has been one of the most important functions of management. In the future this could be even more important. Many forest companies are facing slow market growth along with, cyclical fluctuations in demand, high interest rates and high investment requirements to increase or replace capacity. This paper presents an instrument to aid managers in their strategic planning. A mathematical description of the instrument, a long-term forest sector model, is presented followed by an example of its use in a Swedish case. The model was developed to analyze the impact of cost competitiveness on the structural change of the Swedish forest sector in a 15-25 year perspective. The model is used now by managers in Sweden to produce scenarios for the Swedish forest industry. The output from the model is also used as input for specific enterprise models. The model consists of two symmetric, competing forest sectors--one for the domestic forest sector and one for the competing forest sectors of other countries. Each forest sector covers all activities, ranging from timber growth to the consumption of forest industry products such as paper, sawn wood, and panels. At the end of this paper an application of the model is illustrated by the Swedish forest sector. One conclusion drawn is that since the Swedish forest sector is competing in a world market the development of its profit level compared with competitors is extremely important. Forest Sci. 32:377-397.
Input/Output Models and Forest Resource Supply Constraints Revisited
Authors: Schallau Con H. , Maki Wilbur R. 
Published: April 2024

Abstract
The authors respond to Vincent's (1986) contention that the results of Leontief (demand) and Ghoshian (supply) interindustry models cannot be gainfully compared. His conclusion follows from a misinterpretation of (1) the Dart and Fight I/O analysis of Douglas County, Oregon (1974), and (2) how the supply and demand models differ regarding causal factors and forward/backward linkages. Forest Sci. 32:401-404.
Hiking Values and the Recreation Opportunity Spectrum
Authors: Rosenthal Donald H. , Walsh Richard G. 
Published: April 2024

Abstract
The contingent valuation technique is used to estimate the net economic value of hiking and backpacking in a National Forest in the Front Range of the Colorado Rockies. The study is based on on-site interviews of 202 hikers, conducted during the summer of 1981. The relationship between dollar value and recreation opportunity spectrum (ROS) class reverses when the unit of measure is switched from trips to recreation visitor days. Trips to the more primitive ROS classes have high consumer surplus, but last a long time, thereby, lowering the consumer surplus per recreation visitor day. Forest Sci. 32:405-415.
Water Stress Response After Thinning Pinus contorta Stands in Montana
Authors: Donner Bryan L. , Running Steven W. 
Published: April 2024

Abstract
Seasonal development of leaf water stress in thinned stands of lodgepole pine (Pinus contorta var. latifolia Engelm.) was compared to adjacent controls at three sites in Montana. Each stand was thinned to varying densities in the fall of 1982 or spring of 1983. Pre-dawn leaf water potential measurements were taken monthly in the summers of 1983 and 1984 using the pressure chamber to determine plant water stress differences between thinned and unthinned stands. Late summer leaf water potential was significantly higher (0.17 to 0.35 MPa) in the thinned stands than in the controls. Computer simulation using the DAYTRANS/PSN ecosystem model suggested that 21 percent greater seasonal photosynthesis could occur in these trees as a result of the approximately 0.3 MPa higher plant water potential measured and additional radiation available to remaining trees. Based on estimated carbon budgets, this additional photosynthate could substantially increase the amount of carbon allocated to stem growth in these trees. Forest Sci. 32:614-625.
A MAXMIN Approach to Nondeclining Yield Timber Harvest Scheduling Problems
Authors: Hof John G. , Pickens James B. , Bartlett E. T. 
Published: April 2024

Abstract
This paper investigates an alternative approach to scheduling timber harvests when nondeclining yield is desired. The approach maximizes the minimum harvest during any one time period, across all time periods in the planning horizon. This approach tends to create an even flow harvest pattern, but allows more flexibility than rigid nondeclining yield or even flow constraints. The approach is tested in a case study involving conversion of an unregulated forest into a regulated state. The results suggest that the approach, in combination with other approaches, may have the potential to generate useful solutions to this type of timber harvest scheduling problem. Forest Sci. 32:653-666.
Seasonal Water Relations of Three Gallery Forest Hardwood Species in Northeast Kansas
Authors: Abrams Marc D. , Knapp Alan K. 
Published: April 2024

Abstract
Field and laboratory studies were used to evaluate several water relations characteristics for saplings of three species: hackberry (Celtis occidentalis), a mesic, late successional tree, and bur and chinquapin oak (Quercus macrocarpa and Q. muehlenbergii), more xeric, early successional trees growing in a northeast Kansas gallery forest understory during a dry summer. For all species, maximum stomatal conductance (gwv) (8.9-9.5 mm · s-1) was recorded early in the season when soil moisture was greatest. Seasonally, sunlit leaves generally had significantly higher gwv than shaded leaves. Both gwv and leaf water potential (ψleaf) decreased during the season in each species, with minimum ψleaf values ranging from -2.13 to -2.48 MPa. Seasonally, ψleaf remained consistently higher than the osmotic potential at zero turgor (ψ0π) for each species (minimum values of (ψ0π) ranged from -2.61 to -3.02 MPa). Hackberry, the most mesic species, experienced the largest seasonal decrease in gwv in both shaded and sunlit leaves (69% and 78% reduction, respectively). Moreover, in contrast to the two oaks, a significant seasonal decline in 600 h ψleaf was shown for hackberry. By season's end, hackberry had the lowest gwv and ψleaf values. In contrast, chinquapin oak had the highest late season gwv for sunlit leaves and ψ leaf, suggesting that this species was better able to utilize late season precipitation. Forest Sci. 32:687-696.
Variation in Sapwood Area-Leaf Area Relations Within Two Stands of Lodgepole Pine
Authors: Dean T. J. , Long J. N. 
Published: April 2024

Abstract
Within-stand variation of the ratio between sapwood cross-sectional area and leaf area was investigated for lodgepole pine (Pinus contorta Dougl.) in northern Utah. For both a mature and a sapling stand, we analyzed the changes in sapwood-leaf area ratio with respect to canopy position and location along the bole, both within and below the live crown.
Excluding suppressed trees, sapwood area at the base of the live crown (BLC) was linearly related to leaf area; however, the slope of the regression for the saplings was 40% greater than the slope for the mature trees. This difference was virtually eliminated when sapwood area at BLC was related to a power function of leaf area for all crown classes. Sapwood area increased from the base of the crown to the base of the crown-free bole. For the mature and sapling trees 98% and 91%, respectively, of the variation in sapwood below the live crown was explained using nonlinear regression with the model
SA = β0(L·LA)β¹
where SA = any sapwood cross-sectional area below the live crown, L = distance from the cross section to midway into crown or center of leaf area, LA = total leaf area per tree, and β0 and β1 = regression coefficients. The sapwood-leaf area ratio varied within the crowns of the mature and sapling trees; the maximum ratio occurred toward the base and the top of the crown and the minimum ratio was found at about the center of leaf area. Forest Sci. 32:749-758.
Prediction of Scenic Quality for Southern Pine Stands
Authors: Buhyoff Gregory J. , Hull R. Bruce , Lien John N. , Cordell H. Ken 
Published: April 2024

Abstract
Statistical models which predict scenic beauty from an in-stand viewer perspective were developed for southern pine stands more than 9 years old. These models indicate that stand age, average stand diameter, and stand stocking density are positively related to scenic quality assessments by the general public. However, the models also show that the number of stems in the 1 to 5 inch dbh classes is related to scenic quality in a negative quadratic fashion. The highest scenic quality for stands of differing ages and average tree diameters is when the sapling and pole stocking is between 1,100 and 1,200 per acre, past which scenic quality will decrease. Results also indicate that optimal stand density is dependent upon stand age. Forest Sci. 32:769-778.
Continuing Response of Pinus radiata to Phosphatic Fertilizers Over Two Rotations
Authors: Gentle S. W. , Humphreys F. R. , Lambert Marcia J. 
Published: April 2024

Abstract
Considerable growth responses to two differing phosphatic fertilizers (rock phosphate and superphosphate) applied to Pinus radiata (D. Don) were previously reported by the authors (Forest Science 11, 1965). At that time the experimental site had carried two rotations of trees, the first unfertilized. The same site has now been grown through a similar period of time in the third rotation (to first thinning) with no further fertilizer applications. Growth responses, foliage and soil chemical analyses have been compared with those obtained over the first fertilized rotation. Results showed that tree growth responses have been maintained significantly through two fertilized rotations to the present time by the original 1947 fertilization. The bulk of the phosphorus from both sources is still present in the soil surface horizon, that from rock phosphate mainly as calcium phosphate, and from superphosphate mostly in aluminum- and iron-bound forms. Implications for forest management are that where adequate growth responses can be obtained from a single long-lived fertilizer source, the investment in fertilizer becomes a long-term addition to forest site quality. Cost effectiveness has been compared for both rotations in terms of 1983 dollars. Forest Sci. 32:822-829.
An Econometric Analysis of Residential Demand for Fuelwood in the United States, 1980–1981
Authors: Hardie Ian W. , Hassan Aziz Abu 
Published: April 2024

Abstract
This paper presents an econometric study of residential fuelwood demand in the United States. It is based on a residential energy consumption survey conducted by the U.S. Department of Energy in 1980-81. Estimates are derived of the probability that a particular household will burn wood and of the quantity of wood that will be burned. Aggregate fuelwood demand is predicted for five census regions and for the contiguous United States. The predicted average probability of burning wood is 0.32, and the average predicted quantity burned is 1.57 cords. Residential fuelwood demand is found to be quite responsive to changes in the price of nonwood heating fuel. Forest Sci. 32:1001-1015.
Effects of Interfering Vegetation on Biomass, Fascicle Morphology and Leaf Area of Loblolly Pine Seedlings
Authors: Zutter Bruce R. , Gjerstad Dean H. , Glover Glenn R. 
Published: April 2024

Abstract
Loblolly pine (Pinus taeda L.) seedlings growing with no interfering vegetation were consistently greater in diameter and biomass than those growing with only herbaceous vegetation. Seedling diameter and biomass were more responsive than height to reduction in interfering vegetation. During the first growing season in the field, pine growth appeared to be influenced more by the presence of herbaceous than woody vegetation. For a given seedling age, the proportion of biomass in branches increased as interfering vegetation decreased.
Seedling age and the absence of interfering vegetation each increased the percentage of foliage biomass in four-needled fascicles, fascicle diameter, total length, sheath length, dry weight, and surface area and decreased specific leaf area. Four-needled fascicles from two-year-old seedlings, growing with or without herbaceous vegetation, tended to be greater in diameter, total length, sheath length, dry weight, and surface area and were approximately equal in density to three-needled fascicles.
Leaf area (total needle surface area) was strongly related to groundline basal area and was quite responsive to changes in herbaceous vegetation. The strong relationship between stem diameter and leaf area at several levels of interference suggests that either measure might be used as an indicator of loblolly pine response to interference from other plants. Forest Sci. 32:1016-1031.
The Impact of Chronic Cadmium Exposure on Growth of Pin Oak Seedlings
Authors: Kazimir Janet , Brennan Eileen 
Published: April 2024

Abstract
Two-year-old pin oak (Quercus palustris Muenchh.) seedlings were grown in sand culture and given complete nutrient solution with or without 0.1 μg/ml Cd (as CdCl2) for one or two growing seasons from May to September and the effect on growth determined. Cadmium accumulated primarily in the roots of the seedlings during chronic exposure but was translocated slowly into the shoot over time. Growth of newly planted two-year-old seedlings was stimulated after one year of Cd treatment, but that of established three-year-old seedlings was not affected. The more frequent application of Cd and the larger root system of the older seedlings resulted in a greater Cd accumulation in the root than that associated with growth stimulation. No measurable effect of Cd on tree growth was detected after two successive years of cadmium treatment; however, the percentage of trees exhibiting foliar toxicity symptoms increased. Where Cd treatment was terminated after one year and the trees replanted in uncontaminated sand, leaves continued to show high levels of Cd due to translocation from perennial tissue, but this response was not reflected in any growth change. Forest Sci. 32:1061–1066.