bluuebunny/crossref_metadata_2025_split huggingface dataset:
Contrasting Release Approaches for a Mixed Paper Birch (Betula papyrifera)–Quaking Aspen (Populus tremuloides) Stand
Authors: Zenner Eric K. , Puettmann Klaus J. 
Published: August 2019

Abstract
Early release from competitors can be used to influence the species composition, quality, and rate of development of young stands. Release strategies can vary in intensity, ranging from complete removal of competitors and infrequent future entries (early, heavy, infrequent [EHI]) to lighter entries that are repeated more frequently (early, light, often [ELO]). It is unclear, however, which strategy is more successful for producing high-quality birch sawtimber (Betula papyrifera Marsh.) in mixed stands with aspen (Populus tremuloides Michx.). We evaluated the effects of various release intensities on the growth and mortality of a 16–18-ft-tall natural aspen–paper birch stand in Minnesota following density reductions from 1,500–3,000 trees ac−1 (trees per acre [TPA]) to 750 (ELO750), 500 (EHI500), and 250 (EHI250) TPA. After 6 years, paper birch was overtopped by aspen and contributed only 14% of basal area in control plots, but it occupied all diameter classes and contributed 77–87% of basal area in release plots. The basal area and volume of all paper birch and of only paper birch crop trees (100 largest TPA) were highest in lightly released ELO750 and lowest in control plots. Growth of mean quadratic diameter, basal area, and volume of paper birch was 2–3 times higher in release plots but independent of release intensity. Early release is necessary to maintain paper birch dominance, but there is no short-term advantage among treatment intensities. Long-term growth simulations using the Forest Vegetation Simulator suggest that merchantable timber production was unaffected by release strategy but that the EHI250 strategy produced the most birch sawtimber (40 times as much as in ELO750).
Validation of Spruce Budworm Outbreak History Developed from Aerial Sketch Mapping of Defoliation in New Brunswick
Authors: Taylor Sarah L. , MacLean David A. 
Published: August 2019

Abstract
Aerial sketch mapping (ASM) of annual defoliation provides a means to quantify spruce budworm (Choristoneura fumiferana Clem.) outbreak histories, but accuracy is affected by factors such as navigation and weather conditions. We used ground-based defoliation estimates from 123 permanent sample plots (PSP) in New Brunswick and increment core growth data from a subset of PSPs, to validate ASM estimates of defoliation. From 1985 to 1993, 85% of 332 cases were correctly classified by aerial estimates as nil–light (0–30%) or moderate–severe (31–100%), with the proportion correct varying by measurement year, defoliation severity, and host species. Growth indices generated from 81 visually cross-dated and verified balsam fir (Abies balsamea [L.] Mill.) tree-ring series in 23 PSPs were significantly negatively correlated with aerial-derived cumulative defoliation for 87% of the PSPs, and correlation increased when aerial estimates were combined with ground survey data. We conclude that aerial surveys provide a reasonable estimate of defoliation history to estimate growth reduction.
Regional Analysis of Hardwood Lumber Production: 1963–2005
Authors: Luppold William , Bumgardner Matthew 
Published: August 2019

Abstract
Between 1963 and 2005 hardwood lumber production in the eastern United States increased by more than 50%. Production more than doubled in the northeastern and north central regions while increasing by less than 25% in the southeastern and south central regions. Increased lumber production in the northern regions was facilitated by an expanding sawtimber inventory, relative high volumes of select oak species and hard maple, an expanding kitchen cabinet industry, increased exports, and increased lumber demand by the pallet industry. Hardwood lumber production in the south central region was correlated with hardwood flooring production. When flooring production declined between 1963 and 1982, south central lumber production declined. After 1982 flooring production increased and hardwood lumber production in the south central region followed. By contrast, lumber production in the southeastern region has been tied to the fortunes of the wood and upholstered furniture industries. As furniture imports increased, the demand for lumber by these industries first stagnated and then declined. As a result, lumber production in this region declined between 1982 and 2005. Today, much of the commodity product portions of hardwood-demanding industries are facing international competition. By contrast, a driver of growth in hardwood lumber demand seems to be smaller manufacturers producing custom and semicustom products. These new industries tend to purchase higher-quality lumber but can use a variety of species. Therefore, states or regions with high volumes of timber and a broad composition of species have the greatest potential for future growth in hardwood lumber production.
Dating Tree Mortality Using Log Decay in the White Mountains of New Hampshire
Authors: Fast Andrew J. , Ducey Mark J. , Gove Jeffrey H. , Leak William B. 
Published: August 2019

Abstract
Coarse woody material (CWM) is an important component of forest ecosystems. To meet specific CWM management objectives, it is important to understand rates of decay. We present results from a silvicultural trial at the Bartlett Experimental Forest, in which time of death is known for a large sample of trees. Either a simple table or regression equations that use diameter, species group, and decay class can be used to predict time since mortality for a given log.
New Developments in Biological Control of Mile-a-Minute Weed
Authors: Hough-Goldstein Judith , Lake Ellen 
Published: August 2019

Abstract
The introduced invasive vine mile-a-minute weed Persicaria perfoliata (formerly Polygonum perfoliatum) is continuing to spread throughout the Mid-Atlantic states and beyond, from its initial site of introduction near York, Pennsylvania. This weed frequently interferes with forest regeneration and until recently had few natural enemies attacking it in its introduced range. In 2004, a permit for field release of a host-specific Asian weevil Rhinoncomimus latipes was obtained, and the weevil has since been released in five states. The weevil has established well and is beginning to impact growth and development of the weed.
Quantifying the Risk of Mortality and Damage to Advance Regeneration within the Path of Harvesting Equipment
Authors: Peck JeriLynn E. , Zenner Eric 
Published: August 2019

Abstract
Given the challenges to regenerating white pine, thinning the overstory to release natural advance regeneration has obvious advantages. However, we document here that harvesting traffic poses a substantial threat to advance regeneration, with an 85% chance of mortality for trees in the path of harvesting equipment. Tree size and vigor had no impact on the chance of survival and trees up to 16 ft in height were lost. The risks of mortality or damage did not increase with proximity to harvested trees but did drop off sharply with distance from harvesting equipment tracks. The results indicate that losses due to felling alone were minor and that logging damage to advance regeneration during an overstory harvest could be reduced if harvesting traffic was better contained.
Northern White-Cedar Ecology and Silviculture in the Northeastern United States and Southeastern Canada: A Synthesis of Knowledge
Authors: Hofmeyer Philip V. , Kenefic Laura S. , Seymour Robert S. 
Published: August 2019

Abstract
Sustainability of the northern white-cedar (Thuja occidentalis L.) resource is a concern in many regions throughout its range because of regeneration failures, difficulty recruiting seedlings into sapling and pole classes, and harvesting levels that exceed growth. Management confusion has resulted from the scarcity of research on northern white-cedar ecology and silviculture, particularly because northern white-cedar is an anomalous tree species. This article synthesizes recent and historical northern white-cedar literature, with a focus on ecology, regeneration, cedar-wildlife interactions, and silviculture. Although a number of past studies have produced contradictory findings, some generalizations of use to the practitioner can be made: northern white-cedar is of small stature, slow growing, decay prone except on cliff sites, and found in both early- and late-successional stands. Northern white-cedar appears to be a highly variable species that can adapt to a wide range of environmental stresses. Because management of this resource has proven difficult, northern white-cedar silvicultural guidelines are needed throughout its range.
Diameter-Limit Harvesting: Effects of Residual Trees on Regeneration Dynamics in Appalachian Hardwoods
Authors: Deluca Travis , Fajvan Mary Ann , Miller Gary 
Published: August 2019

Abstract
Ten-years after diameter-limit harvesting in an Appalachian hardwood stand, the height, dbh, and basal area of sapling regeneration was inversely related to the degree of “overtopping” of residual trees. Black cherry and red maple were the most abundant saplings with 416.5 ± 25.7 and 152.9 ± 16.8 stems per acre, respectively. Models of black cherry height and diameter showed significant negative relationships (P < 0.05) with residual tree basal area. In addition, height, diameter, and basal area of dominant and codominant black cherry and black birch saplings were inversely related to residual tree basal area (P < 0.05), as was the basal area of red maple saplings. Alternatively, red maple sapling diameter had a significant positive relationship (P < 0.05) with residual basal area, and height was not significantly affected. Findings suggest that overall stand conditions were most favorable for the development of shade-tolerant red maple, with shade-intolerant species developing well in open areas. However, the long-term development of black cherry may be jeopardized by side shade and canopy cover. Removal of residual trees and subsequent cleaning operations are recommended to increase growth rates of shade-intolerant sapling regeneration.
Foresters' Perceptions of Windthrow Dynamics in Northern Minnesota Riparian Management Zones
Authors: Steil Jeremy C. , Blinn Charles R. , Kolka Randy 
Published: August 2019

Abstract
A survey was mailed to foresters in northern Minnesota to identify their perceptions of what conditions result in higher incidence of windthrow in riparian management zones (RMZ) where the upland has been clearcut. Results indicate that foresters think many variables impact windthrow, often interacting in complex ways. Foresters considered topographic exposure, species, soil moisture, and aspect as the more important factors to consider when trying to mitigate windthrow in RMZs. In general, perceptions and rankings of windthrow factors by foresters are in agreement with the published literature. Based on foresters' perceptions, recommendations are provided to assist forest resource managers in making decisions about retaining trees within streamside RMZs.
Expected Rates of Value Growth for Individual Sugar Maple Crop Trees in the Great Lakes Region: A Reply to John E. Wagner's Comment
Authors: Pickens James B. , Johnson Dean L. , Orr Blair D. , Reed David D. , Webster Charles E. , Schmierer James M. 
Published: August 2019

Abstract
This article is a reply to the comment of Wagner (2009) concerning our article in this issue (Webster et al. 2009). We believe that our use of rate of value growth (RVG), which is analogous to internal rate of return, is acceptable and even preferred for the situation we address. We agree with Wagner that maximization of net present value (NPV) is generally a preferred criterion if certain general conditions exist. As documented in the article, we recommend calculating the RVG and then comparing that value to the relevant threshold interest rate, as selected by the decisionmaker, to make the decision whether to retain a high-quality sugar maple crop tree for another cutting cycle. It is the threshold interest rate that is a true interest rate and that includes, among other things, a risk adjustment premium appropriate for this investment; the RVG was not represented as an interest rate in Webster et al. (2009). We believe RVG is a more appropriate criterion for several reasons: it is widely used by practitioners, closely related previous literature relied on similar measures, take and leave decisions are identical to the NPV criterion for interest rates 4% and above, and the perfect capital markets assumption that leads to NPV being the superior criterion is not satisfied.
Tracking Forest Change and Development Using Low-Cost Remote Sensing Imagery and GIS Integration
Authors: Briggs Nathan A. , Sader Steven A. 
Published: August 2019

Abstract
Conversion of forestland to other uses is occurring in Maine as growing human populations and desire for second homes are exerting development pressures on privately owned forestland. This study was performed to assess forest cover change and conversion to developed uses in a 636,000-hastudy area in Maine. A three-date time series (2000, 2002, and 2006) of Landsat Thematic Mapper data was analyzed to detect forest cover losses, and overall mapping accuracy was determined to be 91%. Forest cover losses (percentage per year) were aggregated for 81 townships and reported foreach time sequence. Rates of forest cover loss differ among townships and for the same township in different time periods. Visual interpretation of forestland conversion using high-resolution images for a subsample of 24 townships showed that 305 of 4,716 harvested forest hectares (6.47%)was converted to developed uses. The study demonstrates the practical use of low-cost remote-sensing imagery and routine interpretation methods for accurate tracking of forest change and quantification of land use conversion. The methods are adaptable to other states to assist decisionmakersin assessing regional and local land use and planning forest conservation measures.
Northern Red Oak, White Oak, and Black Walnut Diameter Growth for the First 3 Years after Thinning in a Mixed Planting
Authors: Gauthier Martin-Michel , Jacobs Douglass F. 
Published: August 2019

Abstract
We established a study to investigate short-term morphological responses of northern red oak (Quercus rubra L.), white oak (Quercus alba L.), and black walnut (Juglans nigra L.) to a 43% basal area reduction in a mixed planting. Although the effect was not statistically confirmed, thinned northern red oak showed a 23% gain in relative diameter growth and a 25% gain in relative crown surface area expansion compared with nonthinned trees; white oak showed gains of 15 and 10%, respectively. Similar trends were found in percentage of basal area increase for northern red oak (45%) and white oak (37%). Black walnut did not appear to respond to thinning and may have been under less competition from first-tier neighbors than the oaks were. Both northern red oak and white oak were in intermediate and suppressed crown classes, whereas black walnut was in a codominant position. Trends from this study suggest that northern red oak and white oak may respond favorably to thinning when found in lower crown classes where the amount of competition from neighboring trees is high.
Sawtimber Yield Tables for Pennsylvania Forest Management Planning
Authors: Gilabert Horacio , Manning Phillip J. , McDill Marc E. , Sterner Steve 
Published: August 2019

Abstract
Models to predict gross and net sawtimber volume per acre for even-aged stands were calibrated for Pennsylvania forests as part of a continuing forest management planning project for Pennsylvania's 2.1 million acres of state forestland. Because of the requirements of the models and limitations of the planning data, the main variable driving the yield models was age. Binary variables were used to shift the sawtimber volume predictions up or down to differentiate yields for 3 site classes, 2 stocking classes, 7 forest types, and 10 ecological regions within the state. The models were fitted using plot-level observations from a continuous forest inventory that has been carried out by the Pennsylvania Department of Conservation and Natural Resources Bureau of Forestry since the 1960s. To apportion the total volume into species groups, proportions were derived of the total sawtimber volume per acre for seven different species groups by forest type and site class for four macro-regions aggregated from the ecological regions within Pennsylvania.
Developing a Stand Hazard Index for Oak Decline in Upland Oak Forests of the Ozark Highlands, Missouri
Authors: Fan Zhaofei , Fan Xiuli , Spetich Martin A. , Shifley Stephen R. , Moser W. Keith , Jensen Randy G. , Kabrick John M. 
Published: August 2019

Abstract
Black oak (Quercus velutina Lam.) and scarlet oak (Quercus coccinea Muenchh.)—two major components (44% of total stand basal area) of upland oak forests—are suffering severe decline and mortality in the Ozark Highlands, Missouri. However, factors influencing their survival (mortality) are not well understood. In this study we quantified how stand and tree-level predisposing factors are associated with survival of black and scarlet oaks. Sixteen-year monitoring data from the Missouri Ozark Forest Ecosystem Project (MOFEP) indicated that overall annual mortality of black and scarlet oaks averaged 2.2 and 1.7%, respectively, three to five times higher than expected (around 0.5%) for white oak, a common associate. For the first 8 years of the study (1990‐1998), survival rates of black and scarlet oaks were similar. Thereafter, the survival rate of black oak declined relative to scarlet oak. Using the classification and regression tree (CART) method we classified black oak and scarlet oak trees into seven and nine risk groups, respectively, that differed significantly in rates of tree mortality. Groups were distinguished based on tree diameter, crown class, and size relative to competitors. An oak decline and mortality hazard index was thus developed as the weighted means of risk group mortality, which can help managers prescribe species-specific silvicultural treatments to help mitigate oak decline and associated mortality.
Composition of Oak Stands in the Illinois Ozark Hills 2 Decades following Light Harvesting and No Cutting
Authors: Holzmueller Eric J. , Groninger John W. , Ruffner Charles M. , Ozier Trevor B. 
Published: August 2019

Abstract
Light harvesting and no cutting are two common management regimes in oak-dominated forests in the Ozark Hills of southern Illinois. We compared changes in overstory stand composition between 1980 and 2000 among forest inventory plots that were lightly harvested after initial sampling and plots that were uncut during the same time period. Total white oak (Quercus alba L.) basal area increased for both management regimes. Black oak (Quercus velutina Lam.) overstory density decreased, and sugar maple (Acer saccharum Marsh.) and American beech (Fagus grandifolia Ehrh.) density increased for both management regimes. Although overall density of oak was maintained by both management regimes, species and diameter class-specific response varied. Additional silvicultural activities may be necessary to sustain oak in both lightly harvested and uncut plots, with light harvesting providing opportunities to at least partially offset costs.
Effects of Cutting Time, Stump Height, and Herbicide Application on Ash (Fraxinus Spp.) Stump Sprouting and Colonization by Emerald Ash Borer (Agrilus planipennis)
Authors: Petrice Toby R. , Haack Robert A. 
Published: August 2019

Abstract
Efforts to eradicate or slow the spread of emerald ash borer (EAB) (Agrilus planipennis Fairmaire [Coleoptera: Buprestidae]) include cutting infested and nearby uninfested ash (Fraxinus spp.) trees. However, ash trees readily sprout after they have been cut, providing potential host material for EAB. In 2004–2005, we conducted studies to determine how different cutting times (midspring, late spring, and late summer), different cutting heights (0–5, 10–15, and 20–25 cm above the ground), and triclopyr (44% active ingredient) stump treatment of green ash (Fraxinus pennsylvanica Marsh.) trees affected subsequent stump sprouting and colonization by EAB. We also cut white ash (Fraxinus americana L.) and black ash (Fraxinus nigra Marsh.) trees 20–25 cm above the ground in late spring. Some stumps of each ash species tested sprouted and were colonized by EAB. All green ash stumps treated with triclopyr died and were not colonized by EAB. Stump sprouting was significantly lower for stumps cut in late spring compared with stumps cut in midspring or late summer. Stump sprouting did not vary significantly among cutting heights. None of the green ash stumps cut in midspring or cut 0–5 cm above the ground were colonized by EAB; however, the frequency of stump colonization by EAB did not vary significantly among cutting times or cutting heights.
Improving the Composition of Beech-Dominated Northern Hardwood Understories in Northern Maine
Authors: Nelson Andrew S. , Wagner Robert G. 
Published: August 2019

Abstract
The natural regeneration that develops following the shelterwood and selection harvesting of northern hardwood stands across the Northeast is often plagued by an overabundance of American beech infected with beech bark disease. This regenerating beech typically dominates and interferes with the regeneration of more desired hardwood species (sugar maple, yellow birch, and red maple), lowering the productivity and value of future stands. We tested factorial combinations of glyphosate herbicide (Accord Concentrate) rate and surfactant (Entrée 5735) concentration to identify an optimal treatment that would maximize beech control while minimizing sugar maple injury. Third-year posttreatment results revealed that glyphosate rate was a more important factor than surfactant concentration in reducing beech abundance and preserving sugar maple. The optimal treatment (0.56‐1.12 kg/ha of glyphosate plus 0.25‐0.5% surfactant) selectively removed 60‐80% of beech stems, whereas sugar maple control was less than 20%. The five dominant hardwood species differed substantially in their susceptibility to the treatments in the following decreasing order: beech > striped maple > yellow birch > red maple > sugar maple. Similar results produced using a backpack mistblower suggested transferability of treatment effects to operational applications using a tractor-mounted mistblower. Our findings indicate that this relatively low-cost and effective treatment can substantially improve the understory composition of northern hardwood stands.
Management Perceptions of Off-Highway Vehicle Use on National Forest System Lands in Appalachia
Authors: Pierskalla Chad D. , Schuett Michael A. , Thompson Katherine A. 
Published: August 2019

Abstract
The purpose of this study was to determine the perceptions of issues related to off-highway vehicle (OHV) use and management tactics among US Forest Service District Rangers on National Forests in the Appalachian region. We determined the differences in perceptions of District Rangers based on different concentrations of OHV managed trails on Ranger Districts. We surveyed 42 District Rangers on 14 National Forests using a modified Dillman mail-back method that resulted in a response rate of 69.1%. The questionnaire was modified from a previous study. Managers with high levels of OHV trail concentrations reported using more varied and additional management tactics to deal with ecological impacts and social issues. Unauthorized trail creation was reported consistently across both levels of OHV trail concentrations. When we compared our findings to earlier results, there were some differences in what managers reported. For example, closing or limiting use was more frequently reported as a management tactic in this study, whereas use of personal contacts was more often selected in the California study.