bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating Scots Pine for Resistance to Endocronartium harknessii
Authors: Burnes T. A. , Blanchette R. A. 
Published: April 2024

Abstract
Seedlings of eight different varieties of scots pine (Pinus sylvestris L.) were evaluated for resistance to pine-pine gall rust Endocronartium harknessii [J.P. Moore] Y. Hiratsuka using a concentrated aeciospore suspension (CAS). The presence or absence of galls on seedlings was recorded 24 wk after inoculation. Seedlings of variety Mongolica were the most resistant with 16% of the seedlings with galls, and Guadalajara and Alpine were the least resistant among the eight with 58% and 56% of the seedlings with galls, respectively. The remaining varieties were intermediately resistant. For. Sci. 37(6):1689-1691.
Ozone Impacts on Seasonal Foliage Dynamics of Young Loblolly Pine
Authors: Stow Tara K. , Allen H. Lee , Kress Lance W. 
Published: April 2024

Abstract
Effects of above- and below-ambient levels of ozone (O3) on the production, abscission, and duration of foliage of young loblolly pine (Pinus taeda L.) grown in open-top chambers were examined in the Piedmont of North Carolina. Assessments of fascicle elongation and number were made at frequent intervals during 1988, 1989, and 1990 for all 1988 primary flushes on the stem and at a branch position. Ozone treatment had little effect on overall foliage production; however, all elevated O3 levels reduced foliage retention. Foliage abscission for most flushes was initiated when cumulative O3 dose exceeded 130 to 220 ppm-hr regardless of crown position for trees exposed to ambient and above-ambient O3 levels. Reductions in leaf area duration of the 1988 cohort were observed at ambient and higher O3 levels. Total leaf area duration was 22 and 25% greater for the stem and branch positions in the charcoal-filtered as compared to nonfiltered treatments. The greater duration in charcoal-filtered chambers resulted from significantly greater retention into the third growing season. Foliage development and ozone responses at the branch position were more representative of the whole crown than those at the stem position. For. Sci. 38(1):102-119.
Comparing Vertical and Horizontal Modes of Importance and Control-Variate Sampling for Bole Volume
Authors: Valentine Harry T. , Bealle Catherine , Gregoire Timothy G. 
Published: April 2024

Abstract
Vertical and horizontal modes of both importance and control-variate sampling for estimating merchantable and total volumes of boles are described and compared. In the horizontal mode, heights are selected at random, and cross-sectional areas are measured. In the vertical mode, cross-sectional areas are selected at random and heights are measured. Estimates obtained by horizontal and vertical control-variate sampling (also known as the critical height method) were equally precise in tests using a proxy taper equation that was linear in cross-sectional area versus height. Both methods gave more precise estimates than did horizontal importance sampling, though the advantage was small for merchantable volume. The performance of vertical importance sampling varied with bole shape. It was the most precise method for some shapes, the least for others. For Sci. 38(1):160-172.
Rate and Depth of Sapwood Occlusion Following Inoculation of Pines with Bluestain Fungi
Authors: Parmeter J. R. , Slaughter G. W. , Chen M. , Wood D. L. 
Published: April 2024

Abstract
Length of sapwood lesions, depth of sapwood occlusion, and proportion of sapwood occluded increased generally but irregularly through the first 9 weeks following inoculation of small (17-32 cm dbh) Pinus ponderosa with Ophiostoma minus or Leptographium terebrantis. No significant increases were detected between 9 and 64 weeks. The average proportion of sapwood depth occluded at 4 weeks ranged from 0.1-0.15 for O. minus and 0.2-0.4 for L. terebrantis. This rate of occlusion was judged inadequate per se to account for development of crown symptoms in trees following mass attack by bark beetles. For. Sci. 38(1):34-44.
Improved Classification of Forest Vegetation in Northern Wisconsin Through a Rule-Based Combination of Soils, Terrain, and Landsat Thematic Mapper Data
Authors: Bolstad Paul V. , Lillesand T. M. 
Published: April 2024

Abstract
Landcover classifications which use evidential and hierarchical decision rules to combine satellite image, soils, and terrain data were compared to standard Landsat Thematic Mapper (TM) based maximum likelihood classifications (MLC) under northern Wisconsin forest conditions. Maximum likelihood classifications employed a visible, near-infrared, and mid-infrared band of TM image data, while a rule-based (combined) approach was used to integrate these data with soil texture information, terrain position, and soil-plant relationships for landcover classification. Comparisons were made for classifications by two analysts for each of two 300 km2 study areas. Accuracies from the combined data method were higher than the MLC method for all classifications. Accuracies averaged 89% for the combined method and 73% for the standard method when areas were classified into 13 landcover classes corresponding to Anderson levels II and III. Pairwise differences of Cohen's Kappa values for the two classification approaches were significantly different (P &lt; 0.10) for all combinations of study area and analyst. For. Sci. 38(1):5-20.
Thinning and Nitrogen Fertilization in a Grand Fir Stand Infested with Western Spruce Budworm. Part II: Tree Growth Response
Authors: Wickman Boyd E. , Mason Richard R. , Paul H. Gene 
Published: April 2024

Abstract
The effects of thinning and nitrogen fertilization on tree growth in a grand fir (Abies grandis [Dougl.] Forbes) stand infested with western spruce budworm (Choristoneura occidentalis Freeman) were evaluated over 5 years by a replicated split-plot experiment. Fertilization treatments resulted in significantly reduced defoliation and significantly heavier biomass of shoots and foliage for the last 3 years of the study. There were, however, 30% fewer buds on fertilized grand fir midcrown branches at the end of the study. Height growth of fertilized trees was significantly greater than unfertilized trees 3 to 5 years after treatment and was almost double that of controls. Radial growth measured at breast height and base of live crown was significantly greater for fertilized trees 3 to 5 years after treatment; 5 years after treatment, radial growth of thinned trees also was significantly greater than the controls. Trees thinned and fertilized had almost double the growth of controls 2 to 5 years after treatment. Fertilized trees apparently produced fewer buds m-2 of foliage but more foliage per shoot than budworm larvae could destroy, and this resulted in significantly increased tree growth. The results of the study have implications for using fertilization as a management option for some budworm outbreaks. For. Sci 38(2):252-264.
Effects of Fall Fertilizer Applications on Mitotic Index and Bud Dormancy of Loblolly Pine Seedlings
Authors: Williams Hans M. , South David B. 
Published: April 2024

Abstract
A series of studies examined the effects of fall fertilization with diammonium phosphate (DAP) on mitotic index and bud dormancy [as measured by mean days to budbreak (DBB)] of two half-sib seed sources of loblolly pine. The first study tested different rates of DAP (0, 67, and 202 kg N/ha), the second study compared DAP with ammonium nitrate, and the third study examined the effect of different application dates (September 28, October 19, and November 9). An increase in mitotic index of unfertilized seedlings was observed during October and was due to developmental activity which follows initial budset. Differences in mitotic index were observed between families in all three studies. Overall, the Georgia family has a higher mitotic index, but in one study, the Virginia family had higher values in the spring. Both families tended to reach a minimum level of mitotic index at the same time (mid- to late December). However, the Virginia family reached maximum rest (as measured by days to budbreak) about 1 to 2 weeks prior to the Georgia family. Fertilization with DAP in the fall (after budset in September) did not delay the progression of the bud dormancy cycle as measured by days to budbreak in a greenhouse. The overall effect of fall fertilization on increasing the mitotic index was temporary and only lasted for about three weeks after fertilization. These findings indicated that a direct relationship may not exist between the bud dormancy cycle and mitotic index. For. Sci. 38(2):336-349.
Root Growth Potential and Starch Differences in Seedlings of Six Families of Genetically Improved Loblolly Pine
Authors: Rose Robin 
Published: April 2024

Abstract
The relationships among root growth potential, total fresh weight, and starch levels of six genetically improved families of loblolly pine (Pinus taeda L.) were examined during a test of root growth potential, with special focus on clarifying changes in starch concentrations as determined by destructive analysis. Seedlings were operationally grown and root-wrenched in a nursery, lifted in January and subjected to 14 days of cold storage at 3°C (38°F), then placed in a tank system in a greenhouse under extended 16-hr days and 30°-16°C (85°-60°F) day-night temperatures. Measurements taken over a 30-day period showed that (1) the percentage of starch initially in the roots was not related to root growth potential expression after 30 days, (2) the starch in new white lateral roots after 30 days was not related to root growth potential, and (3) seedlings that produced new roots tended to have more total starch in all plant parts than those that did not. For. Sci. 38(2):448-456.
A Comparison of Distance-Dependent Competition Measures for Height and Basal Area Growth of Individual Conifer Trees
Authors: Biging Greg S. , Dobbertin Matthias 
Published: April 2024

Abstract
The effect of competition on height and diameter² growth of individual conifer trees was examined. In this paper we modeled growth of individual trees as a product of potential growth reduced by competition. We investigated a number of competition indices that incorporate tree sizes and distances from neighbors, evaluated over varying competition zones. For these indices the reduction in mean square error relative to no competition index was used to judge performance. The performance of these indices varies by species and growth component (height or diameter² growth), but performance was generally better for tolerant white fir than for intolerant ponderosa pine. Additional competition measures that incorporate estimated crown parameters were developed and shown to improve on many of the traditional competition measures especially for ponderosa pine and Douglas-fir. For white fir, basal area performed well, but not as well as the individual tree competition indices that incorporate estimated crown parameters. We found that expanding the search zone did not improve our ability to estimate competitive effects. Choosing competitors with a height angle gauge was generally superior to selecting them with a DBH angle gauge. Results are summarized by species, type of competition index, and competition evaluation zone. For. Sci. 38(3):695-720.
Air Pollution Stress in the Bavarian Forest?
Authors: Visser Hans , Molenaar Jaap 
Published: April 2024

Abstract
Two objections expressed by Kandler (1992) to our results in a recent article (Visser and Molenaar 1992) are discussed. We argue that, although we did not use all data available from the fir stands under consideration, inclusion of the other measurements would not have changed our conclusions. We also point out that, contrary to Kandler's remark, deposition of pollutants (wet rather than dry deposition) may not be ignored as a potential stress factor in the Bavarian Forest. For. Sci. 38(4):870-872
Modeling Soil Temperature Effects on In Situ Decomposition Rates for Fine Roots of Loblolly Pine
Authors: Ruark Gregory A. 
Published: April 2024

Abstract
A study was conducted to quantify the relationship between soil temperature and fine root decomposition. Undisturbed soil cores containing root systems of loblolly pine seedlings were incubated in the lab under field capacity moisture conditions at constant soil temperatures of 15° and 25°C. Some seedling root systems were allowed to decompose in situ outside, where soil moisture and temperature were recorded. Laboratory and outside in situ results were compared to decomposition rates for seedling roots that were washed, air-dried, and reburied outside in mesh bags. Laboratory decomposition rates of the seedling root system, which contained fine laterals and a small taproot, averaged 31% and 44% weight loss annually, while annual rates of only the fine lateral root component averaged 57% and 66% loss of total weight at 15° and 25°, respectively. Average annual Q-10s of 1.4 and 1.2 were calculated between 15° and 25° for whole root systems and lateral roots alone. Lab incubation results were used to construct a regression model for fine root decomposition as a function of cumulative average monthly temperature. The model was validated against data on the root systems that were allowed to decompose in situ outside. Decomposition of this material after 1 yr was 43% complete for the whole root system and 60% complete for laterals. The observed remaining weight at various time intervals was accurately predicted from the regression model. After 1 yr, roots in the buried bags displayed a weight loss similar to the outdoor in situ samples. However, their decomposition rate was linear, whereas both outdoor and incubator in situ samples followed a curvilinear decay path. FOR. SCI. 39(1):118-129.
Genetic Variation Among Lake States Balsam Poplar Populations Is Associated with Geographic Origin
Authors: Riemenschneider Don E. , McMahon Bernard G. 
Published: April 2024

Abstract
Variation among populations of balsam poplar from Minnesota, Wisconsin, and Michigan (the Lake States) in tree height, phenology, and sylleptic branching was associated with geographic origin based on bivariate correlation, canonical correlation, principal component, and cluster analyses. Ninety percent of the joint variation in five traits was explained by two principal components, the first associated with late season growth and tree height, the second associated with number of sylleptic branches. Populations were delineated into northwestern, central, and southeastern clusters based on principal component one and two coordinates using Ward's minimum variance method. Populations from the south-eastern cluster grew taller, produced more late season leaves, and set bud later than populations from the northwestern and central dusters. FOR. SCI. 39(1):130-136.
Frequency Domain Tree-Ring Standardization
Authors: Van Deusen Paul C. , Reams Gregory A. 
Published: April 2024

Abstract
Prior to modeling tree-ring variation from climatic variables, an effort is made to standardize the tree-ring series by removing nonclimatic variance. A number of methods for standardizing tree-ting series in the frequency domain are presented along with a method for reducing end-fit problems. A technique for controlling the stiffness of a smoothing spline using frequency domain considerations is derived using matrix theory, and the spline is shown to be similar to other frequency domain methods. The results presented here elucidate earlier developments and allow for a more general application of frequency domain smoothing procedures. FOR. SCI. 39(1):55-65.
Retrospective Early Tests of Pinus sylvestris L. Seedlings Grown Under Five Nutrient Regimes
Authors: Eriksson Gösta , Jonsson Alena , Dormling Ingegerd , Norell Lennart , Stener Lars-Göran 
Published: April 2024

Abstract
Seedlings belonging to 36 families from a partial diallel mating between 11 parents of Scots pine (Pinus sylvestris L.) were cultivated for three growth periods in growth chambers at five nutrient levels in the range 5-45 mg N/liter. The ratios between N:K:P were always 100:65:13. Several growth and growth component characters were assessed, mainly during the third growth period. Additive genetic correlations between these characters and growth of other full-sibs from the same parents assessed at ages 10-28 in two adjacent field trials in southeastern Sweden were estimated. Estimates of the additive genetic correlations were obtained by calculating Pearson product moments of phenotypic values adjusted for nongenetic effects. Tests of independence between the genetic values in the phytotron and in the field trials were performed using rank correlation of the estimated GCA values. The lowest nutrient level gave low or negative genetic correlation coefficients with field data. For the four higher nutrient levels the genetic correlation coefficients between growth chamber data and field data increased with age of the field material. The strongest correlations were obtained with growth increments between years 13-23 and 23-28 (0.8-1.0). The standard errors of the estimates of the genetic correlation coefficients mostly varied between 0.2-0.5. FOR. SCI. 39(1):95-117.
Effect of Partial Defoliation on Growth and Carbon Exchange of Two Clones of Young Populus trichocarpa Torr. & Gray
Authors: Bassman John H. , Zwier John C. 
Published: April 2024

Abstract
A controlled environment study was performed to test the effect of two levels of a single partial defoliation on growth, dry weight partitioning, and gas exchange of two contrasting clones of Populus trichocarpa Torr. & Gray. One clone was from a moist habitat in western Washington and the other from a dry habitat in eastern Washington. Trees were partially defoliated (40% or 80% of leaf area removed) at the 25-leaf stage. Height, diameter, leaf area, and rates of net photosynthesis, dark respiration, transpiration, and leaf conductance were determined at the time of defoliation and 3 wk, and 5 wk after defoliation. Biomass distribution was determined following harvest 5 wk after defoliation. Defoliation caused reductions in height, diameter, and biomass in both clones compared to control plants. However, reductions were not proportional to level of defoliation, suggesting compensatory growth was occurring. Total biomass was reduced by 30% and 27% in the western and eastern Washington clones respectively by a 40% defoliation, and 43% and 35% following an 80% defoliation. A 40% defoliation caused an increase in the proportion of biomass in lateral branches of trees of the western Washington clone. An 80% defoliation caused an increase in the proportion of biomass in lateral branches of both clones. Both defoliation treatments reduced leaf area on the main stem but increased leaf area on lateral branches. Both levels of defoliation reduced root biomass of both clones. Specific leaf weight of leaves produced after defoliation in both clones increased. Partial defoliations of 40% and 80% had no effect on net photosynthesis of either clone. Rates of dark respiration in both clones were either unaffected by defoliation or slightly reduced. For. Sci. 39(3):419-431.
The Effects of GA3 and Organic Solvents on Acclimatization of Tissue Culture Propagated Black Cherry (Prunus serotina Ehrh.) Plantlets
Authors: Kavanagh Kathleen L. , Lee Dong-Hun , Drew Allan P. , Maynard Charles A. 
Published: April 2024

Abstract
Both gibberellic acid (GA3) and chilling were effective in inducing stem elongation of black cherry plantlets during acclimatization. At the rate of 100 mg/l, a foliar spray of GA3 was effective in stimulating stem elongation, but the effect was temporary. Most plantlets elongated to approximately 9 cm, but then set a resting bud. At rates above 200 mg/l, GA3 severely stunted root growth. An organic solvent solution enhanced the stem elongation response to GA3. When plantlets were treated with 100 mg/l GA3 in 0.2% DMSO and 54% ethanol, reinitiation of stem elongation was quicker, and bud set was delayed. Although the combination of GA3 and organic solvents induced stem elongation, it did not fully substitute for a chilling period. The minimum chilling period required to induce terminal bud break was 6 wk, and an additional 4 to 6 wk induced more rapid terminal bud break and stem elongation. For. Sci. 39(4): 644-654.
U.S. Policy and Canadian Lumber: Effects of the 1986 Memorandum of Understanding
Authors: Wear David N. , Lee Karen J. 
Published: April 2024

Abstract
A 1986 Memorandum of Understanding on softwood lumber imports (MOU) between Canada and the United States required that provincial governments levy export taxes on softwood lumber shipped to the United States. This agreement, with subsequent amendments, influenced trade from 1987 until it was abandoned by Canada in October of 1991. This paper investigates the market impact of the MOU, first by estimating an aggregate impact model of the Canadian share of the U.S. softwood lumber market and then by examining the implied price, quantity, and welfare effects. While the study shows the anticipated gains to U.S. producers of softwood lumber and losses to Canadian producers, U.S. consumer and efficiency costs were high, and the net of Canadian profit loss and export tax revenue was strongly positive. In addition, the net impact on market share appears to have persisted through 1990, in spite of considerable change in the policy's structure. These and other results should provide information for ongoing policy debate. For. Sci. 39(4):799-815.
A Mixed Integer Linear Programming Approach for Spatially Optimizing Wildlife and Timber in Managed Forest Ecosystems
Authors: Hof John G. , Joyce Linda A. 
Published: April 2024

Abstract
This paper presents mixed integer linear programming formulations for land allocation that optimize spatial layout for a single time period and that have the property that the number of integer variables is a linear function of the level of spatial resolution. The formulations focus on timber, edge-dependent wildlife, and area-dependent wildlife. They account for the amount of edge, the fragmentation of habitat area, and a habitat area threshold for minimum viable population size. Habitat area connectivity is modeled as a probabilistic condition. A case example demonstrates the approaches and includes landscape characteristics such as terrain, hiking trails, campgrounds, and rivers, which result in different productivities over the landscape and obstacles to wildlife habitat area connectivity. For. Sci. 39(4):816-834.
Notes: A Continuous-Time Markov Chain for Early Selections
Authors: Magnussen Steen 
Published: April 2024

Abstract
A discrete stepwise Markov chain for predicting relative performance of early selections at time of harvest is transformed into a continuous-time Markov chain by a simple transformation to a canonical form. Asymptotic predictions for t → ∞ are made possible. Prediction errors are derived from an autoregressive scheme and assumptions of multinominal one-step ahead errors. For. Sci. 39(4):845-850.