bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability of the TMS-evoked potential in dorsolateral prefrontal cortex
Authors: Gogulski Juha , Cline Christopher C , Ross Jessica M , Parmigiani Sara , Keller Corey J
Published: April 2024

We currently lack a reliable method to probe cortical excitability noninvasively from the human dorsolateral prefrontal cortex (dlPFC). We recently found that the strength of early and local dlPFC transcranial magnetic stimulation (TMS)–evoked potentials (EL-TEPs) varied widely across dlPFC subregions. Despite these differences in response amplitude, reliability at each target is unknown. Here we quantified within-session reliability of dlPFC EL-TEPs after TMS to six left dlPFC subregions in 15 healthy subjects. We evaluated reliability (concordance correlation coefficient [CCC]) across targets, time windows, quantification methods, regions of interest, sensor- vs. source-space, and number of trials. On average, the medial target was most reliable (CCC = 0.78) and the most anterior target was least reliable (CCC = 0.24). However, all targets except the most anterior were reliable (CCC > 0.7) using at least one combination of the analytical parameters tested. Longer (20 to 60 ms) and later (30 to 60 ms) windows increased reliability compared to earlier and shorter windows. Reliable EL-TEPs (CCC up to 0.86) were observed using only 25 TMS trials at a medial dlPFC target. Overall, medial dlPFC targeting, wider windows, and peak-to-peak quantification improved reliability. With careful selection of target and analytic parameters, highly reliable EL-TEPs can be extracted from the dlPFC after only a small number of trials.
Ethnicity differences in geometric remodelling and myocardial composition in hypertension unveiled by cardiovascular magnetic resonance
Authors: Georgiopoulos Georgios , Faconti Luca , Mohamed Aqeel T , Figliozzi Stefano , Asher Clint , Keehn Louise , McNally Ryan , Alfakih Khaled , Vennin Samuel , Chiribiri Amedeo , Lamata Pablo , Chowienczyk Philip , Masci Pier-Giorgio
Published: April 2024

Aims

Hypertensive patients of African ancestry (Afr-a) have higher incidences of heart failure and worse clinical outcomes than hypertensive patients of European ancestry (Eu-a), yet the underlying mechanisms remain misunderstood. This study investigated right (RV) and left (LV) ventricular remodelling alongside myocardial tissue derangements between Afr-a and Eu-a hypertensives.

Methods and results

63 Afr-a and 47 Eu-a hypertensives underwent multi-parametric cardiovascular magnetic resonance. Biventricular volumes, mass, function, mass/end-diastolic volume (M/V) ratios, T2 and pre-/post-contrast T1 relaxation times, synthetic extracellular volume, and myocardial fibrosis (MF) were measured. 3D shape modelling was implemented to delineate ventricular geometry. LV and RV mass (indexed to body-surface-area) and M/V ratio were significantly greater in Afr-a than Eu-a hypertensives (67.1 ± 21.7 vs. 58.3 ± 16.7 g/m2, 12.6 ± 3.48 vs. 10.7 ± 2.71 g/m2, 0.79 ± 0.21 vs. 0.70 ± 0.14 g/mL, and 0.16 ± 0.04 vs. 0.13 ± 0.03 g/mL, respectively; P < 0.03). Afr-a patients showed greater basal interventricular septum thickness than Eu-a patients, influencing LV hypertrophy and RV cavity changes. This biventricular remodelling was associated with prolonged T2 relaxation time (47.0 ± 2.2 vs. 45.7 ± 2.2 ms, P = 0.005) and higher prevalence (23% vs. 4%, P = 0.001) and extent of MF [2.3 (0.6–14.3) vs. 1.6 (0.9–2.5) % LV mass, P = 0.008] in Afr-a patients. Multivariable linear regression showed that modifiable cardiovascular risk factors and greater end-diastolic volume, but not ethnicity, were independently associated with greater LV mass.

Conclusion

Afr-a hypertensives had distinctive biventricular remodelling, including increased RV mass, septal thickening and myocardial tissue abnormalities compared with Eu-a hypertensives. From this study, modifiable cardiovascular risk factors and ventricular geometry, but not ethnicity, were independently associated with greater LV myocardial mass.
Anterolateral thoracotomy with partial sternotomy: a feasible approach for treating the complex pathology of the aortic arch
Authors: Yamanaka Katsuhiro , Hasegawa Shota , Kawabata Ryo , Shiraki Hironaga , Chomei Shunya , Inoue Taishi , Tsujimoto Takanori , Miyahara Shunsuke , Takahashi Hiroaki , Okada Kenji
Published: April 2024

OBJECTIVES

Our goal was to review our surgical experiences in patients with complex pathologies of the aortic arch who have undergone anterolateral thoracotomy with a partial sternotomy (ALPS).

METHODS

From October 2019 to November 2023, a total of 23 patients underwent one-stage repairs of complex pathologies of the aortic arch through the ALPS approach. The mean age was 61.9 ± 16.7 years old. The aortic pathologies were as follows: aorta-related infection in 11 (aorto-oesophageal fistula: 4, graft infection: 6, native aortic infection: 1); aortic dissection in 9 including shaggy aorta in 2, non-dissecting aneurysm in 1, and coarctation of the aorta (CoA) in 2.

RESULTS

Eighteen patients underwent aortic replacement from either the sinotubular junction or the ascending aorta to the descending aorta; 1 patient underwent it from the aortic root to the descending aorta (redo Bentall procedure and extensive aortic arch replacement); 3 patients underwent it from the aortic arch between the left carotid artery and left subclavian artery to the descending aorta; and 1 patient underwent a descending aortic replacement. Ten patients underwent omentopexy, latissimus dorsi muscle flap installation or both procedures. The hospital mortality rate was 13.0% (3/23). The overall survival and freedom from aortic events were 73.3%±10.2% and 74.1%±10.2%, respectively, at the 3-year follow-up. There was an absence of aorta-related deaths, and no recurrent infections were identified.

CONCLUSIONS

The short-term outcomes using the ALPS approach for the treatment of complex pathologies of the aortic arch were acceptable. Further studies will be required to determine the long-term results.
Low-dose colchicine for atherosclerosis: long-term safety
Authors: Nidorf Stefan Mark , Ben-Chetrit Eldad , Ridker Paul M
Published: April 2024

Low-dose colchicine (0.5 mg daily) is now FDA-approved for secondary prevention in patients with coronary disease and will be increasingly prescribed in clinical practice. In this State-of-the-Art Review, data were collated from contemporary systemic reviews of case reports, drug registries, and placebo-controlled trials that assessed specific issues of safety related to the continuous use of colchicine in a range of clinical settings to inform physicians, pharmacists, and patients of the absolute risks of continuous use of low-dose colchicine, including among individuals taking statin therapy. Based upon these collective data, it is concluded that aside mild diarrhoea on initiation of colchicine that typically subsides in the vast majority of patients within a week of therapy, continuous use of low-dose colchicine is well tolerated and very safe. It does not affect renal, liver, or cognitive function, has no adverse effects on bleeding, wound healing, fertility, or pregnancy, and does not increase risks of cancer, serious infection, or cause-specific mortality. When appropriately prescribed to patients without significant renal or hepatic impairment, reports of myelosuppression, myotoxicity, and serious drug–drug interactions are rare and no more frequent than placebo, including in patients taking statin therapy. Physicians, pharmacists, and patients can be reassured that in the absence of significant renal or hepatic impairment continuous use of low-dose colchicine can be used safely in patients with atherosclerosis for the purpose of reducing cardiovascular risk.
Allelopathic Potential of Coniferous Species to Old-Field Weeds in Eastern Quebec
Authors: Jobidon Robert
Published: April 2024

Phytotoxicity of Abies balsamea (L.) Mill., Picea mariana (Mill.) BSP., Pinus resinosa Ait., Pinus divaricata (Ait.) Dumont, and Thuya occidentalis L. fresh leaf and leaf litter leachates were evaluated on the germination and growth of four weed species: Phleum pratense L., Poa pratensis L., Agropyron repens (L.) Beauv., and Epilobium angustifolium L. Three dilutions of leachates were used for the germination tests. Germination of all weed species was inhibited in proportion to the dilutions used. Fresh leaf leachates of A. balsamea and P. resinosa were most inhibitory to germination. P. pratense was usually less affected by the treatments than were the other three species. Germination or E. angustifolium and P. pratensis was delayed by the different solutions; germination of P. pratense was delayed only by fresh leaf leachates of A. balsamea and P. divaricata. Height growth and root elongation of A. repens, P. pratensis and P. pratense were inhibited by most extracts. P. mariana leaf leachates were the most inhibitory to height growth and root elongation. All seedlings treated with P. mariana leaf leachates exhibited severe root necroses which affected normal root development. Laboratory experiments suggested that allelopathic weed control, using coniferous leaf litter or fresh leaves, could aid in reforestation of abandoned fields by reducing undesirable competition. Forest Sci. 32:112-118.
Econometric Analysis of the Factors Influencing Forest Acreage Trends in the Southeast
Authors: Alig Ralph J.
Published: April 2024

Econometric models of changes in land use acreages in the Southeast by physiographic region have been developed by pooling cross-section and time series data. Separate acreage equations have been estimated for the three major private forestland owner classes and the three major classes of nonforest land use. Observations were drawn at three or four different points in time for the 21 Forest Survey Units in the Southeast. Of the variables examined, population and personal income measures were the major significant explanatory variables in the land use equations. Forest Sci. 32:119-134.
Predicting Site Hazard to Fusiform Rust
Authors: Froelich R. C. , Snow G. A.
Published: April 2024

Nine plantations of slash pine (Pinus elliottii Engelm. vat. elliottii) were established in 1974 in southern Mississippi to study conditions affecting incidence of fusiform rust. Variables studied included climate, seed source, soil properties, pine growth, fungus and host phenology, abundance of aeciospore-producing galls and telia, number of basidiospores trapped, and the spatial relationships of oaks to the plantations. From 1974 through 1978, the amount of pine infection varied considerably by year according to frequency of rain or nights with prolonged high relative humidity. There also were large, but inconsistent, differences in annual infection among sites, due to a complexity of factors. Seed source, soil properties, and pine growth were unrelated to site hazard. The hazard of each area depended on the relationships of oaks to the pine plantations—how near they were, what directions from the plantation, and the number of oaks. Criteria are presented for differentiating among low-, medium-, and high-hazard sites for fusiform rust. Forest Sci. 32:21-35.
A Dynamic Cost and Factor Demand Analysis for the Pacific Northwest Lumber and Plywood Industries
Authors: Merrifield David E. , Singleton William R.
Published: April 2024

A dynamic capital adjustment model is used to describe the Pacific Northwest lumber and plywood industries. The industries' derived demand for stumpage, labor, and capital inputs along with the behavior of costs over output levels are assumed dependent on the quasi-fixed nature of industry capital. Results obtained from data over the period 1954-80 suggest that own and cross-price elasticities of derived demand generally increase as the industries adjust towards long-run desired capital levels. Measures of short, intermediate, and long-run input requirement elasticities revealed relatively constant proportions of stumpage requirements to output levels in both industries, relatively constant proportions of labor to output in the plywood industry, yet relatively volatile employment levels in the Pacific Northwest lumber industry over the long run. Further, adjustments in capital levels appear to have had only a limited effect on the behavior of production costs in the two industries. Forest Sci. 32:220-233.
Distribution of Biomass Within Small Tree and Shrub Form Quercus gambelii Stands
Authors: Clary Warren P. , Tiedemann Arthur R.
Published: April 2024

Gambel oak (Quercus gambelii Nutt.) occupies approximately 3.5 million ha in the states of Arizona, Colorado, New Mexico, and Utah. It is becoming recognized as an important fuelwood resource. Design of appropriate management strategies requires information on the biomass distribution characteristics within these stands. Biomass components of eight Gambel oak small tree and shrub form stands (clones) were sampled in Utah. Stem densities ranged from 5,000 to 34,000 per ha of clone. Mean stem diameters varied from 36 to 117 mm. Live stems averaged 4,992 g including dead branches, while standing dead stems averaged 1,347 g. Live biomass per occupied hectare averaged 124,388 kg including 40,702 kg of bole. The ratio of aboveground to belowground live biomasses was unusually low—44:56. Total aboveground and belowground biomass including detritus was 184,292 kg per hectare of clone. Forest Sci. 32:234-242.
Fire Induced Tree Mortality in a Colorado Ponderosa Pine/Douglas-fir Stand
Authors: Wyant James G. , Omi Philip N. , Laven Richard D.
Published: April 2024

The impact of a fall season prescribed surface fire on Douglas-fir and ponderosa pine mortality during the first 22 months following fire was evaluated using discriminant function analysis. Crown scorch, expressed as a percentage of the prefire live crown length, was the single best determinant of tree mortality. Stem charting on the least impacted quadrant is also a relevant variable in mortality determinations. Larger diameter trees of both species withstood proportionally greater stem and crown damage than smaller trees. Crown consumption indicators added substantially to the discriminating power of the functions, but prefire live crown and maximum scorch height were not important variables. Within the same size range, there was little evidence of important differences between ponderosa pine and Douglas-fir in the levels of crown and stem damage that induce mortality. Forest Sci. 32:49-59.
Eastern Dwarf Mistletoe Seed Storage, Germination, and Inoculation of Spruce Seedlings
Authors: Livingston William H. , Blanchette Robert A.
Published: April 2024

Eastern dwarf mistletoe seed used for inoculation of Picea mariana and P. glauca had better germination (i.e., appearance of a red radicle) and radicle growth when stored at subfreezing temperatures (- 10°C vs. + 4°C) and high humidity for at least 10-12 weeks, and such seed remained viable for at least 40 weeks. Usually 25 percent or less of the seeds had radicle growth longer than 1 min. In greenhouse inoculations, most spruce seedlings (57 of 61) became infected if the radicle made contact with the stem. Forest Sci. 32:92-96.
A Re-Evaluation of the Site Burden Concept When Forest Land Value is Maximized
Authors: Rideout Goug , Hof John G.
Published: April 2024

Comparative statics of the Faustmann (1849) forest land value model are used to analyze the site burden measure of forest tax incidence. The analysis focuses on the importance of allowing management variables to respond to forest taxation, and the results are obtained within the context of land value maximization. General results are derived by applying the Envelope Theorem and ancillary comparative statics to the Faustmann formulation. The paper defines a site burden error term that is shown to increase at an increasing rate with respect to tax rates when management decisions are assumed fixed. Graphical analysis of the timber yield tax is performed, and a specific empirical example of the yield tax, using planting density and rotation age as management variables, demonstrates that site burden error is not necessarily trivial. Forest Sci. 32:511-516.
Changes in Mortality and Size-Class Spatial Distribution Patterns in Pre-Closure and Post-Closure Conifer Plantations
Authors: Ghent Arthur W. , Franson Susan E.
Published: April 2024

Spatial distribution patterns of first-year deaths, and of living tree vigor classes (formed by dividing height-measurement distributions at their approximate one-third points to demarcate shortest, intermediate, and tallest trees) were studied by joins-testing in 5- to 10-year-old pre-closure rectangular lattices (trees aligned in both rows and columns) of white spruce (Picea glauca (Moench) Voss) and red pine (Pinus resinosa Ait.). Frequencies of observed joins between members of the same vigor class exceeded statistical expectations for random adjacency in 86 of 100 pre-closure comparisons, 42 of these excesses being statistically significant. Only one of the 14 comparisons of opposite trend achieved borderline significance. Thus the preponderant tendency was for members of all pre-closure vigor classes to occur in clumps with other members of the same class. This pattern is interpreted as reflecting gradients of soil conditions, a conclusion supported by a comparable preponderance of joins-count deficits between members of vigor classes separated by at least two ranks. In contrast, rectangular lattice plantings of 17- and 18-year-old post-closure red pine showed consistently significant deficits of joins between members of the most vigorous (largest diametered) class of living trees, indicating a natural trend to regular distributions of the largest trees without the intervention of thinning. Significant excesses of joins were observed between these most vigorous trees and the spaces left by presumptive first-year deaths, also a complete reversal of the pre-closure pattern. Forest Sci. 32:559-575.
Optimal Hedging in Lumber Futures Markets
Authors: Deneckere Raymond , Buongiorno Joseph , Bark Sun Il
Published: April 2024

This paper investigated the effectiveness of the lumber futures market in hedging unexpected price variations. The related optimum hedge ratio, i.e., the fraction of the cash position that should be hedged to minimize risk, was also studied. The measure of hedging effectiveness used was the correlation between cash and futures price, conditional on information available at the time of hedging. The analysis of weekly price data showed that during the period June 1980 to February 1985 optimum use of the lumber futures market could have reduced the variance in gain or loss by 50 to 90 percent. Longer hedges were generally more effective and so were those liquidated near the closure of the futures contract. The best strategy was to hedge the cash position entirely, except for hedges liquidated within 8 weeks of contract closure for which hedge ratios of 60 to 80 percent were most effective. Forest Sci. 32:634-642.
Aboveground Phenology in North Florida Slash Pine Plantations
Authors: Hendry L. C. , Gholz H. L.
Published: April 2024

Seasonality of aboveground growth and reproduction, its relationship to environmental conditions, and the composition and development of the understory were studied for 2 years on young and mature slash pine (Pinus elliottii var. elliottii Engelm) plantations in north Florida. Despite relatively mild environmental conditions year-round, tree and understory growth were strongly unimodal, peaking in late spring-early summer when air and soil temperatures and precipitation were highest. Length of spring shoots in pines appeared to be directly related to soil temperature and precipitation of the previous fall-winter when winter buds were forming. Presence of summer shoots appeared to be dependent upon the environmental conditions of the current growing season, age of the tree, and branch position in the canopy. Site preparation practices, notably chopping and burning, in part dictated the species composition and development of the understory until about midrotation, at which time shading and forest floor development became more important. Fine root studies reflected the same compositional changes as seen above ground. Although aboveground understory biomass was a small fraction of pine biomass by midrotation, pine and understory fine root biomass and foliar turnover rates were comparable. Forest Sci. 32:779-788.
A Mechanistic Computer Model of Mountain Pine Beetle Populations Interacting with Lodgepole Pine Stands and Its Implications for Forest Managers
Authors: Raffa Kenneth F. , Berryman Alan A.
Published: April 2024

A computer simulation model based on laboratory and field studies of mountain pine beetle (Dendroctonus ponderosae Hopkins) interactions with lodgepole pine (Pinus contorta var. latifolia) is presented. The experimental results provide the basis for the underlying assumptions and equations concerning host resistance, beetle numbers, and nutrient availability. This simulation is not intended to predict numerical levels in any particular region, but instead provides a basis for considering how host and beetle factors can interact to affect population behavior.

The model generates patterns of population behavior characteristic of D. ponderosae and other primary bark beetle species, and shows a variable relationship of population density with population growth. The system has two equilibrium points, one of which is stable, and the other is unstable. The unstable equilibrium represents a threshold that separates regions of qualitatively different population behavior (endemic from epidemic). Each stand is characterized by a unique population outbreak threshold, and this value is strongly affected by age class.

The simulation model was used to evaluate management practices for controlling D. ponderosae outbreaks. The most important factors were found to be those that directly affect host vigor. Stand thinning seems to provide the most effective long-term protection from beetle outbreaks. Forest Sci. 32:789-805.
Effects of Herbaceous Weed Control Using Herbicides on a Young Loblolly Pine Plantation
Authors: Zutter B. R. , Glover G. R. , Gjerstad D. H.
Published: April 2024

On an Upper Coastal Plain site in east-central Alabama, herbicides were used to create three herbaceous vegetation treatments based on duration and degree of herbaceous vegetation control during the first two growing seasons following planting of loblolly pine (Pinus taeda L.): (1) low—near complete control for two seasons; (2) medium—single broadcast application of a herbicide at the beginning of the first growing season only; (3) high—no herbaceous vegetation control. Woody vegetation was periodically controlled on all plots. These treatments created a wide range of residual herbaceous vegetation. Soil moisture and first-year height and diameter growth of loblolly pine were negatively correlated with the level of herbaceous vegetation. A wide range in soil moisture was noted for comparable levels of herbaceous vegetation across treatment plots. This demonstrates the necessity for researchers examining effects of competition on pines to also assess soil moisture or soil attributes affecting water holding capacity. First-year seedling diameter was found to be more responsive than height to the level of herbaceous vegetation and associated levels of soil moisture. However, tip moth incidence was greater at the lowest levels of herbaceous vegetation, possibly reducing height growth below its potential. First-year pine growth was most highly correlated to soil moisture level in late August, when soil moisture was lowest, than any other sample date. During the first growing season, pine growth on medium and high herbaceous level plots fell behind that on low level plots (near complete control) once herbaceous biomass approached 25 to 45% of September biomass on high herbaceous level plots (no control). Effects of herbaceous weed levels on pine growth are attributed in part to differences in soil moisture and their effects on seedling water status and physiological processes. Forest Sci. 32:882-899.
Estimating Defoliation Using Stratified Point Intercept Sampling
Authors: Cooper Robert J. , Dodge Kevin M. , Whitmore Robert C.
Published: April 2024

A method of estimating percent defoliation is presented whereby foliage measurements are taken on a plot using a sighting tube and compared to foliage present at the same points on the same plot in a base year. Since measurements are not independent, a nonparametric procedure using McNemar's statistic is used to estimate percent defoliation and its standard error. Percent defoliation is estimated for an entire plot by dividing the plot into canopy height categories. An example is provided. For. Sci. 33(1): 157-163.
Approximating Precision in Simulation Projections: An Efficient Alternative to Monte Carlo Methods
Authors: Gertner George
Published: April 2024

Estimates of the precision of predictions made with simulation models are often desired to gauge the variability of predictions, place confidence intervals around the predictions, and test hypotheses. However, estimates of precision are not usually calculated for large multicomponent simulation models because of the huge computational costs. To overcome this, the error propagation method can be used to approximate the precision of simulation estimates. The method was used in this study to approximate the variance of predictions made with a variation of the individual tree growth and yield model, STEMS (Stand and Tree Evaluation and Modeling System). The method was compared with a crude Monte Carlo method for obtaining simulation variances. At its worse, the error propagation approximation of standard deviation diverged from the Monte Carlo approximation by 16% for a 50-year projection. The technique reduced execution time for calculating the variances by a factor of almost 2,000. For. Sci. 33(1):230-239.
Analysis of the 3/2 Power Law of Self-Thinning
Authors: Zeide Boris
Published: April 2024

The 3/2 power law states that the relative rate of self-thinning with respect to biomass growth per unit area is a universal constant equal to two. The law could be true in two cases: (1) when all factors of stand dynamics unaccounted for by the law (in particular, change in plant form and change in crown closure) are nonexistent; and (2) when the effects of the unaccounted factors on the rate of self-thinning cancel each other. As the presented reasons and evidence show, the major neglected factors indeed oppositely affect the rate of self-thinning. In general, however, these factors rarely balance each other, and the rate predictably changes with age, species, site quality, and other factors. The limiting line of self-thinning does not have any constant slope (on the log-log scale); generally, this line is a curve. A realistic model of self-thinning should be more inclusive than the law and particularly reflect the change in crown closure, or gap dynamics. An analysis of the law suggests the use of tree size as a predictor of their number; the utilization of the fact that diameter is better correlated with crown width and tree number than tree mass; and the development of a more adequate form of expressing allometric relationships than the elementary power function. For. Sci. 33(2):517-537.
Percentile-Based Distributions Characterize Forest Stand Tables
Authors: Borders B. E. , Souter R. A. , Bailey R. L. , Ware K. D.
Published: April 2024

A satisfactory characterization of stand tables need not require a prior mathematical probability distribution. The method described here uses a system of percentiles defined across the range of the stand table. Based on a uniform distribution of tree frequency between adjacent percentiles, stems-per-acre are proportioned into diameter size classes. For. Sci. 33(2):570-576.
Estimation of the Diameter Increment Function or Other Tree Relations Using Angle-Count Samples
Authors: Lappi Juha , Bailey Robert L.
Published: April 2024

A formula is derived for the bias when an angle-count sample is used to estimate the mean of a tree variable that is correlated with the breast height diameter. This bias occurs, for instance, if average increment is estimated with increment cores from an angle-count sample. Estimation of mean increment for a given initial diameter is studied further by assuming that increments are log-normally distributed, in which case the sampling distribution is a mixture of three log-normal distributions. An estimate obtained by weighting observations inversely to the basal area (i.e., with the estimated tree frequency) compares favorably in simulations with a parametric estimate derived from the sampling distribution of diameters. If increments are regressed on the initial diameters, then weighting proportionally to the initial basal area and inversely to the current basal area gives smaller bias and standard deviation of parameter estimates than weighting inversely to the current basal area alone. For. Sci. 33(3):725-739.
Estimating Potential Density from Thinning Experiments and Inventory Data
Authors: Sterba H.
Published: April 2024

By combining and modifying the Competition Density Rule of Kira et al. (1953), Reineke's concept of stand density index (Reineke 1933), and Assmann's theory of maximum basal area, a method to estimate potential density of sites has been developed. From the data of 11 thinning experiments it has been shown that the maximum stand density index, estimated in this way, is well correlated with the gross volume yield at a given height and thinning regime. Data from an inventory show that with this method of estimating and characterizing maximum stand density it is possible to evaluate differences of gross volume yield that would never have been detected if only yield tables had been used. For. Sci. 33(4):1022-1034.
In Vitro Responses of Conifer Adventitious Shoots and Calli Inoculated with Gremmeniella abietina
Authors: Abdul Rahman Nik N. , Diner Alex M. , Skilling Darroll D. , Karnosky David F.
Published: April 2024

Larix decidua adventitious shoots were inoculated with axenic vegetative hyphae and conidia of Gremmeniella abietina. Dense host surface mycelial growth and needle necrosis occurred after inoculation with vegetative hyphae and conidia within two weeks and four weeks, respectively. The pathogen completed its life cycle by producing pink conidial pustules on some infected propagules within one month. Light and scanning electron microscopic examination showed that hyphae penetrated commonly through or between epidermal cells and rarely through the stomates. Differential responses were evident within and between shoot clones. Inoculated calli of resistant L. leptolepis and Abies balsamea showed less mycelial growth than did L. decidua calli. Inoculation success was a function of spore inoculum density. In vitro responses correlated well with known in vivo responses. Our rapid (30-d) in vitro resolution of host resistance suggests that these methods may reduce the time required for evaluating relative disease resistance as compared to traditional field tests. For. Sci. 33(4):1047-1053.
Two-Dimensional Analysis of Logging Tail Spars
Authors: Pyles Marvin R. , Pugh Edwin V.
Published: April 2024

A beam-column analysis of a skyline-logging tail spar was formulated and an example analysis made of a second-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) spar (15.-in. dbh) rigged at 40 ft. The analysis takes into account the taper of the spar tree, the flexibility of the base of the spar, and the eccentric restraining load at the top provided by guylines. Allowable skyline tension on the tail spar is shown to vary with skyline angle and guyline pretension. An optimum guyline pretension that produces the greatest capacity in the spar tree was found to be within a range attainable by hand tightening. The variation of allowable skyline tension with rigging height and spar diameter also is shown. For. Sci. 33(4):971-983.
Effect of Natural Inbreeding on Variance Structure in Tests of Wind-Pollination Douglas-Fir Progenies
Authors: Sorensen Frank C. , White Timothy L.
Published: April 2024

Studies of the mating habits of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) have shown that wind-pollination families contain a small proportion of very slow-growing natural inbreds.

The effect of these very small trees on means, variances, and variance ratios was evaluated for height and diameter in a 16-year-old plantation by systematically deleting from analyses the shortest individuals in wind-pollination (W) and diallel (D) progenies of six parent trees. The progenies were growing together in a common field test. The D population served as a control (no inbreds).

The low-vigor trees in the W population type gave a downward bias to means and an upward bias to within-plot and family x block variance estimates. Amount of bias differed among W families. Before deletion, estimates of additive genetic variance and heritability for height in the W test were about one-third and one-sixth the estimates from the D test. Deleting the shortest 5 to 8% of the trees from the W population did not remove all the discrepancy, but it did result in much closer agreement between W and D tests. For the D test alone, deletion of the smallest trees had a negligible effect on estimates of additive genetic variance and heritability. For. Sci 34(1):102-118.
Hybridization of the California Firs
Authors: Critchfield William B.
Published: April 2024

Four groups of firs (sections, in the most recent classification of Abies) are represented in California. Crossing within these sections is possible and even easy, and in two of the sections intergrading populations between highly crossable taxa are wide-spread in California. An exception is A. amabilis, a Northwestern fir that has not been crossed with other species in the same section (Grandes: A. concolor, A. grandis) or in other sections (e.g., Nobiles: A magnifica). Crossing species in different sections is usually difficult or impossible. The genetic isolation of A. bracteata, an endemic species classified as a monotypic subgenus or section, may be nearly complete: two probable hybrids with A. concolor died at a few years of age. A few putative hybrids from intersectional crosses between species in Grandes and Nobiles died within months of germination. Intersectional crosses with firs outside California (two Mexican and four Eurasian species) all failed except A. concolor x A. religiosa, which produced numerous healthy hybrids. The common occurrence of genetic barriers in Abies is at odds with the long-held view that it is easy to hybridize fir species. For. Sci. 34(1):139-151.
Genetic Variation in Leaf Morphology and Plant and Tissue Water Relations During Drought in Cercis canadensis L
Authors: Abrams Marc D.
Published: April 2024

Genetic variation in plant and tissue water relations in response to drought, and in leaf morphology, were examined in greenhouse-grown Cercis canadensis L. (eastern redbud) seedlings originating from seed obtained in three contrasting habitats: a relatively xeric Kansas prairie, a Kansas gallery forest understory, and a relatively mesic Indiana understory. Kansas prairie redbud maintained significantly greater leaf conductance (gwv) during a 13-day drought than did Kansas and Indiana understory redbud, despite similar decreases in leaf water potential (Ψleaf) in all three sources. Moreover, Kansas prairie redbud had significantly lower osmotic potentials at full and zero turgor compared to Indiana redbud at both the early and later stages of drought. Kansas understory redbud was the only source to undergo a significant decrease in relative water content at zero turgor and the bulk modulus of elasticity during drought. Kansas prairie redbud leaves were smaller and thicker and had higher specific leaf mass (i.e., more xerophytic) than understory redbud leaves. Kansas understory redbud had intermediate characteristics in terms of gwv; at the early to middle stages of drought, osmotic potentials at high and low Ψleaf and leaf area and thickness compared to Kansas prairie and Indiana understory redbud. These results suggest that genetically controlled physiological and morphological adaptation has occurred in redbud that should facilitate its survival in greatly contrasting habitats. For. Sci. 34(1):200-207.
Selecting Foliage and Growth Variables for Relating Insect Defoliation to Coniferous Tree Growth
Authors: Nichols Thomas J.
Published: April 2024

Correlations between estimators of foliage levels and basal area growth were compared for use in regression equations relating western spruce budworm defoliation to growth on 192 Douglas-fir and grand fir trees. Foliage terms that included one- to four-year-old foliage had the highest correlations, and adjusting foliage estimates to account for decreased foliage production improved correlations. Calibrations from a stand growth model predicting nondefoliated growth yielded the most precise estimates, as did adjusting growth estimates for annual weather impacts using a model including soil and weather factors. For. Sci. 34(1):236-242.
Activity Analysis in Forest Planning
Authors: Paredes V. Gonzalo L. , Brodie J. Douglas
Published: April 2024

Linear programming has been the primary mathematical programming technique for multiple-use land management planning. Over the last two decades, forest planning research has emphasized modeling and computational issues of linear programming, rather than it uses for valuation and economic analysis. This paper shows that postoptimal activity analysis provides an effective tool for economic valuation of multiple-resource outputs and production factors. Marginal value curves are easily derived for both market and nonmarket outputs, and for production factors. This and other information are useful in comparing production alternatives and provide a basis for the economic rationale currently sought in multiple-use planning. Also, an efficient joint cost allocation scheme is proposed for use as an accounting system to track efficiency of production for market goods and to audit for rational evaluation of nonmarket goods. For. Sci. 34(1):3-18.
Changes in Loblolly Pine Seedling Root Growth Potential, Dry Weight, and Dormancy During Cold Storage
Authors: DeWald Laura E. , Feret Peter P.
Published: April 2024

Loblolly pine (Pinus taeda L.) seedlings from a Virginia nursery were lifted once per month between October and February during the 1983 and 1984 lifting seasons and held in cold storage at 2°C for 3, 6, 9, and 12 weeks. Following cold storage, root growth potential (RGP) and root and shoot characteristics were compared to freshly lifted seedlings. New root growth was similar despite significant differences in dry weight and shoot activity between cold-stored and freshly lifted seedlings. Seedlings placed in cold storage prior to the accumulation of 500 chilling hours in the nursery stored poorly. Cold storage success of seedlings in the spring was variable. For. Sci. 34(1):41-54.
The Influence of Soil Moisture on Eucalyptus Leaf Litter Moisture
Authors: Hatton Thomas J. , Viney Neil R. , Catchpole E. A. , De Mestre Neville J.
Published: April 2024

An experiment was carried out to test the assumption that surface soil moisture affects fine dead fuel moisture. A randomized block design was used to test the response in Eucalyptus leaf moisture to two levels of soil moisture over a range of exposures to the sun, wind, and soil surface. Soil moisture clearly influenced daily leaf fuel moisture minima and maxima. The effect on daily minima was most pronounced for the bottom of the litter layer, which was shielded from the sun and wind and in contact with the soil. The effect of soil moisture on daily fuel moisture maxima was most pronounced for exposed samples. The responses in fuel moisture due to exposure and soil moisture were compared with fine fuel moistures predicted by three fuel moisture models. The various treatment combinations of soil moisture and exposure produced fuel moistures that varied too widely for any of the tested fuel moisture models to be consistently most accurate. For. Sci. 34(2):292-301.
Accuracy Testing and Estimation Alternatives
Authors: Gregoire Timothy G. , Reynolds Marion R.
Published: April 2024

The relation between the Freese (1960) accuracy test and the related test proposed by Reynolds (1984) is examined and a three-way decision rule is recommended as a circumspect alternative to the accept/reject decision rule commonly employed. Further alternatives are proposed in the form of point and interval estimates for parameters of the error distribution under scrutiny. The effect of bias correction on the test procedures and estimators is analyzed and simulated. Conditional bias correction following a pretest is shown to behave equivalently to unconditional bias correction when sample size is not too small. When errors are nonnormal, all tests and estimators degrade considerably, and the problem becomes severe for large sample sizes. For. Sci. 34(2):302-320.
Optimum Age For Family Selection for Growth in Genetic Tests of Loblolly Pine
Authors: McKeand S. E.
Published: April 2024

To increase the efficiency of the breeding and testing program of the North Carolina State University-Industry Cooperative Tree Improvement Program, an analysis of 18 first-generation genetic tests of loblolly pine (Pinus taeda L.) was conducted to guide the decision of when growth should be assessed in advanced generation genetic tests. The biologically optimum age (where gain per year was maximized) for selecting families from these tests ranged from 3 to 10 years of age. Under reasonable assumptions for age-age correlations and heritability changes over time, expected gain per year in the breeding program was the greatest for selection between 6 and 8 years. The higher present value of gains from younger selection ages would lower the optimum selection age to 4 years or earlier. For. Sci. 34(2):400-411.
Predicted and Actual Capacity Changes in the Pulp and Paper Industries of Developed Market Economies: A Test of Rational Expectations
Authors: Buongiorno Joseph , Calmels Patrice
Published: April 2024

A comparison was done of expected and actual changes of production capacity in the pulp and paper industries of 14 major producing countries. Tests were done to determine whether the predictions used all available information in an optimal manner (full rationality). The results showed that this was not the case for 29 to 86% of the countries, depending on the length of the forecast and commodity group. Another set of tests was then done to determine if whatever information used by forecasters was used efficiently (partial rationality). Unbiasedness, a necessary condition of partial rationality, was rejected for 29 to 79% of the countries considered, depending on forecast length and commodity group. Aggregation of countries into regions did not eliminate the bias. The general tendency was for forecasters to overestimate increases in capacity. For. Sci. 34(3):606-620.
Three-Dimensional Forest Growth Model Relating Tree Size, Tree Number, and Stand Age: Relation to Previous Growth Models and to Self-Thinning
Authors: McFadden George , Oliver Chadwick D.
Published: April 2024

A generalized three-dimensional model for tree growth containing tree size, number of trees per area, and stand age on the three axes can be shown to incorporate three previous models in the theoretical absence of differentiation and self-thinning. The previous models, each incorporating two of the three axes, are: the sigmoid growth models of tree size/stand age; the relation of tree size (volume or diameter)/tree number; and the reverse-J-shaped mortality relation of maximum tree number/stand age. Information developed from one two-dimensional model can be transferred to the other models using the three-dimensional response surface to interpret the growth trajectory of stands undergoing differentiation and self-thinning. For. Sci. 34(3):662-676.
Volume Estimation from Sample Tree Counts with Certain Individual Tree Volume Equations
Authors: Lynch Thomas B.
Published: April 2024

Since rapid inventories of forester areas are often required, it is desirable to reduce tree measurements for volume estimation when individual tree volume equations of certain commonly used types are available. In some cases it is possible to do so by altering the usual horizontal point sampling procedure so that sample trees are chosen with probability exactly proportional to the equations being used to obtain individual tree volume. In certain other cases, estimators are presented that combine counts of fixed-size and variable-size plots. One of the methods is compatible with local volume equations used in the Turnbull-Hoyer tarif system. For. Sci. 34(3):677-697.
Variation of Stem Rust Resistance in a Lodgepole Pine Provenance-Family Plantation
Authors: Yanchuk Alvin D. , Yeh Francis C. , Dancik Bruce P.
Published: April 2024

The pattern of inheritance of stalactiform blister rust (Cronartium coleosporioides Arth.) and western gall rust (Endocronartium harknessii Y. Hiratsuka) resistance in lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) was examined in a 10-year-old progeny trial of 214 open-pollinated families from 24 provenances in British Columbia. Provenance means and family-within-provenance means differed significantly for the two stem rusts. A positive relationship between elevation of provenance and provenance means for stalactiform blister rust score was found (R² = 0.34, P < 0.01). Coastal provenances had the highest infection level for western gall rust. The heritability estimates appropriate for mass, family, and provenance selection on stalactiform blister rust resistance were 0.21 ± 0.11, 0.42 ± 0.17, and 0.74 ± 0.31, respectively. The heritability estimates appropriate for mass, family, and provenance selection on western gall rust resistance were 0.14 ± 0.09, 0.34 ± 0.16, and 0.77 ± 0.33, respectively. The large positive genetic correlation (0.49 ± 0.27) between stalactiform blister rust and western gall rust indicates that selection will simultaneously improve both traits. For. Sci. 34(4):1067-1075.
Heritability, Age-Age Correlations, and Inferences Regarding Juvenile Selection in Jack Pine
Authors: Riemenschneider Don E.
Published: April 2024

Heights of jack pine trees from 101 open-pollinated families were measured at ages 1, 2, 3, 5, and 7 years. Age-age genetic and phenotypic correlations, and age-related fluctuations in heritability were evaluated to determine the optimal age for juvenile selection. Simple linear regressions of genetic and phenotypic age-age correlations on the natural log of the ratio of the two ages were significant (r² = 0.84 and 0.93 respectively). Genetic age-age correlations were greater than corresponding phenotypic correlations, particularly at longer age intervals. Heritability for tree height was highest at age 1 year, lowest at age 2, and intermediate thereafter. Results suggests that selection as early as age one would be an efficient strategy for improving rotation-age growth. For. Sci. 34(4):1076-1082.
Growth of Whiteleaf Manzanita (Arctostaphylos viscida Parry)
Authors: Minore Don , Weatherly Howard G. , Means Joseph E.
Published: April 2024

To describe the growth of whiteleaf manzanita (Arctostaphylos viscida Parry) on a variety of sites, stem-analysis techniques commonly used to analyze height growth of trees were applied to 47 open-grown shrubs in southwestern Oregon. Present crown dimensions were measured, and past stem lengths for each year of growth were determined by dissecting the longest stem. A model was fit to describe stem length as a function of plant age and stem length at age 10. Stem height, crown area, and crown volume were then related to length of the longest stem. The resulting equations can be used to predict the growing space that will be occupied by open-grown shrubs at any time through age 20. For. Sci. 34(4):1094-1100.