bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crop Tree Release Improves Competitiveness of Northern Red Oak Growing in Association with Black Cherry
Authors: Schuler Thomas M. 
Published: August 2019

Abstract
In 1993, a crop tree study was established in a pole-sized stand consisting of black cherry (Prunus serotina Ehrh.) and northern red oak (Quercus rubra L.). Black cherry was the predominant species in the stand and appeared to be on the verge of virtually eliminating northern red oak based on its greater height growth potential. To assess crop tree management for maintaining the competitiveness of oak in this situation, the stand was compartmentalized into treated and untreated areas and crop trees were selected. In the treated areas, crop trees received a three- or four-sided crown-touching release. Individual tree characteristics were measured following the growing seasons of 1993 and 10 years later. Crop tree release resulted in slowing the height growth of codominant black cherry, but not northern red oak. Ten-year mean height growth of northern red oak exceeded that of released black cherry, but not that of unreleased black cherry crop trees. Crown expansion and diameter at breast height (dbh) growth also increased as a result of crop tree release for both species, but black cherry clear stem development was suppressed. Based on increment core analysis, dbh growth of released northern red oak crop trees in 2003 was about twice that of unreleased northern red oak, although black cherry treatment related differences in radial growth were no longer present. Ten years after crop tree release, northern red oak crown class distribution improved and black cherry crown class distribution was unchanged. These results suggest crop tree management will improve northern red oak competitiveness in pole-sized stands when growing in association with black cherry and, perhaps, other fast growing species.
Control of Hay-Scented Fern by Mowing
Authors: de la Crétaz Avril L. , Kelty Matthew J. 
Published: August 2019

Abstract
Hay-scented fern (Dennstaedtia punctilobula) is a native species that can invade and dominate the forest understory, after thinning and intensive deer browsing. Fern colonies form a dense cover 60 to 80 cm high that intercepts light and inhibits tree seedling regeneration. Hay-scented fern can be controlled with herbicides, but some landowners (both public and private) seek alternative methods. We investigated mowing as a possible method of fern control. We tested different mowing schedules and measured the response of ferns (frond length and density) and of natural regeneration and planted seedlings. Mowing the ferns twice in one growing season (first in June when the fern fronds had reached their full height and again in August) led to a significant reduction in frond length during the next two growing seasons compared to untreated controls. Mowing four times over 2 years reduced both length and density of ferns. Mean density of naturally established tree seedlings was four times greater on these treatment plots compared to controls, but with great variability among plots. Red oak (Quercus rubra) and sugar maple (Acer saccharum) seedlings planted the year after mowing showed greater survival and height growth compared to controls.
Short-Term Effects of Silvicultural Treatments on Microsite Heterogeneity and Plant Diversity in Mature Tennessee Oak-Hickory Forests
Authors: Jackson Samuel W. , Harper Craig A. , Buckley David S. , Miller Bradley F. 
Published: August 2019

Abstract
Growing emphasis on sustainability has increased the demand for information on effects of forest management on species diversity. We investigated the hypothesis that plant diversity is a function of microsite heterogeneity by documenting plant diversity and heterogeneity in canopy cover, light, and soil moisture produced by four silvicultural treatments during the first growing season following treatment: prescribed burning, wildlife retention cut with prescribed burning, wildlife retention cut, and shelterwood cutting. Treatments and controls were randomly assigned within four relatively undisturbed, 70–90-year-old oak-hickory stands. Heterogeneity in canopy cover and photosynthetically active radiation was greatest after shelterwood cutting, whereas the wildlife retention cut resulted in less removal of canopy trees and a smaller increase in heterogeneity of these factors. The addition of prescribed burning enhanced the effects of the wildlife retention cut. Prescribed burning alone had the least impact on heterogeneity of these factors. Soil moisture variability appeared to be independent of treatments. Shelterwood cutting increased first-year herbaceous plant diversity, and this increase was likely due, in part, to increased heterogeneity in canopy cover, light, and seedbed condition. These first-year results partially support the hypothesis that plant diversity is a function of microsite diversity in these forests. Long-term monitoring is underway.
A Simple Technique for Estimating Board Foot Volume Yields in Appalachian Hardwoods
Authors: Brooks John R. , Wiant Harry V. 
Published: August 2019

Abstract
A simple whole stand yield equation based solely on basal area per acre for sawtimber-sized trees and average dominant height was found to provide reasonably accurate estimates of board foot (International) yield in Appalachian hardwoods. Separate parameter estimates were obtained for mesophytic hardwood and mixed oak remeasurement plot data and the yield tables of Schnur (Schnur, G.L. 1937. Yield, stand and volume tables for even-aged upland oak forests. USDA Tech. Bull. 560). Estimates of board foot yield per acre for the remeasurement plot data were within 10% of observed values for stands over 30 years old and within 5% for stands over 45 years old. A separate model form based on the same two input variables was developed for Schnur’s yield table data for site index classes 50–80. Estimates of board foot yield were within 10% of tabular values for stands over 45 years old, regardless of site index class.
The Effect of Timber Value Information on Pennsylvania's Private Forest Landowner: A Case Study
Authors: Brubaker Roy D. , Finley James C. , McDill Marc E. 
Published: August 2019

Abstract
Six case studies involving private forest landowners in two central Pennsylvania counties explore whether or not participants accurately estimate the present and future value of their timber and the impact improved growth and value data had on their perception of forest value. Methods included testing initial participant estimates, attitudes, and objectives against cruise data collected on each tract and discussing discrepancies between the two information sets (predicted and measured). Participants were relatively accurate at predicting approximate present values, but less adept at predicting probable future values and apportioning appropriate values to contributing factors of future value growth. The relative value of these and other findings from the case studies to education and outreach efforts on the part of resource professions—particularly in regards to generating forest landowner interest in forest management—is discussed. North. J. Appl. For. 23(4):234 –240.
Conventional and Mechanized Logging Compared for Ozark Hardwood Forest Thinning: Productivity, Economics, and Environmental Impact
Authors: Becker Peter , Jensen Jason , Meinert Dennis 
Published: August 2019

Abstract
Replicate 4-ac plots in a 70-year-old upland oak forest on slopes averaging 30 percent in southeastern Missouri were harvested by conventional (chainsaw + skidder) and mechanized (small tracked skid steer + feller-buncher and harvester + forwarder) logging equipment.The heavy thinning prescribed by a crop tree management approach removed an average of 1,300 ft3 or 40 tons per acre of pole wood and sawlogs, leaving an average basal area of 36 ft2/ac. The harvester/forwarder was the most productive (ft3/production hour),and the small feller-buncher the least, being the only system whose (unreplicated) production cost exceeded revenue. Production costs (excluding mobilization, overhead, and profit) of the conventional and harvester/forwarder systems were not statistically different on average, but the lowestcost of the latter was 14% less than that of the conventional system. The frequency of residual trees experiencing substantial bole damage was not significantly different among logging technologies, but the harvester/forwarder did have a higher incidence of substantial crown damage.The area of exposed mineral soil did not differ significantly among technologies, and soil compaction sufficient to impede rooting was rare. Lack of site and operator replication and incomplete cost analyses over a limited time prohibit generalization of these conclusions. North. J. Appl. For. 23(4):264 –272.
Methodology for the Re-location of Permanent Plot Markers Using Spatial Analysis
Authors: Small Erin D. , Wilson Jeremy S. , Kimball Alan J. 
Published: August 2019

Abstract
A well-designed method of establishing, maintaining, and remeasuring permanent plots plays an essential role in long-term data collection. This article describes the re-location of plots set up 25 years earlier using conventional techniques of paced distances and compass directions. As a result, we needed to design and use a method for re-locating plot markers originally established without the benefit of spatial coordinates. Preplanned ground searches using a GIS, digital orthophotoquads, landmark maps, and aerial photographs improved our plot location efficiency and success. In 2003, we were able to re-locate 90% of the plots set up in 1978 to measure the vegetation dynamics after a fire in Baxter State Park, Maine. The spatial coordinates of these permanent plots were documented for future measurement. Lessons learned and techniques developed for this project can facilitate the re-location of permanent plots in other studies and can also be used to improve the documentation of newly established plot locations.
Taper, Volume, and Weight of Small Black Cherry and Red Maple Trees in West Virginia
Authors: Brooks John R. 
Published: August 2019

Abstract
Taper, cubic foot volume, and green weight equations to multiple top diameters were developed for the main bole portion of small-diameter black cherry (BC; Prunus serotina Ehrh.) and red maple (RM; Acer rubrum L.) trees in northern West Virginia. Sample trees were selected from the 2- to 5-in.-diameter class and ranged from 30 to 60 ft in total height. Existing published cubic foot volume equations provided estimates from 6 to 40% lower than estimates from the proposed model form, depending on species and tree size. Based on the published weight equations selected for comparison, differences between the estimates from the proposed models and from the published model with the smallest weight difference from a pool of candidate models, total bole green weight was underestimated from 5 to 93% for BC and from 0.4 to 25% for RM, depending on species and tree size.
Growth and Site Index of White Pine in Relation to Soils and Topography in the Glaciated Areas of Ohio
Authors: Brown James H. 
Published: August 2019

Abstract
Multiple regression equations were developed using topographic and soil factors for predicting growth and site index of white pine growing on old-field sites in the Wisconsin-aged glaciated areas of northern and western Ohio. Correlations between height growth of trees below the breast high (bh) annual growth increment and bh and above were not statistically significant and growth and site index estimates were made using age at bh and growth from the bh annual increment to the growing tip. The best estimates of heights and site index were obtained when data were subdivided into two groups. For plots having 0–10% slopes, two regression equations were developed for predicting height growth: one containing slope shape and depth to soil mottling and the other adding percent clay in the B2 soil horizon to the equation. Those equations accounted for 67 and 73%, respectively, of the variation in heights of trees and 35-year site index ranged from 62 to 82 ft, with the best growth on convex-shaped slopes having the greatest depth to mottling and the lowest clay content. For sites having slopes greater than 10%, one equation was developed containing slope position and slope percent as variables. That equation accounted for 72% of the variation in heights of trees, and site index ranged from 71 to 81 ft, with the best growth on plots at the bottom of slopes having the lowest slope percent.
Impacts of Skidding Traffic Intensity on Soil Disturbance, Soil Recovery, and Aspen Regeneration in North Central Minnesota
Authors: Zenner Eric K. , Fauskee Jeremiah T. , Berger Alaina L. , Puettmann Klaus J. 
Published: August 2019

Abstract
We investigated the effects of different levels of ground-based skidding traffic intensity on soil disturbance, characterized by resistance to penetration (RP) within the top 15 cm of soil, as well as soil recovery, regeneration, and early growth of quaking aspen (Populus tremuloides Michx.) suckers 3 years after a clearcut with reserves summer harvest. Equipment traffic was confined to a network of skid trails, and a GPS was used to determine the number of skidder passes at each of 30 sampling points that were preestablished along an anticipated disturbance gradient ranging from landings to skid trails to areas off skid trails. Thirty-one percent of the harvest area was affected by skid traffic, and up to 603 passes were recorded for a plot. RP increased nonlinearly with the number of passes and reached highest levels at the soil surface. Three years after harvest, soils showed partial recovery in the upper 10-cm layer, with full recovery of the surface layer (0–5 cm depth) when affected by 4 or fewer passes. The deepest layer (10–15 cm), however, showed little recovery since harvest. Sucker density, height, and basal diameter of all suckers and height, basal diameter, and dbh of the tallest suckers were significantly reduced with increasing traffic intensity but were not related to increases in RP. Predicted reduction of sucker density was approximately one-third after 10 passes; reductions of height, basal diameter, and dbh were between 1.5 and 2.5% at 10 passes and 3.5 and 6.5% at 25 passes. Because skidding traffic affected only a limited portion of the stand, the productivity of the future aspen stand was not severely impaired, at least in the very short term.
Application of Nursery Testing in Long-Term White Spruce Improvement Programs
Authors: Weng Yuhui , Tosh Kathy , Park Yill Sung , Fullarton Michele S. 
Published: August 2019

Abstract
Polycross-pollinated white spruce (Picea glauca [Moench] Voss) families were evaluated in field and retrospective nursery tests in 1989, 1991, and 1992, respectively. Height growth was measured at age 10 for the field tests and at ages 1 to 6 for the retrospective nursery tests. Except for a few cases, the family mean correlations between nursery and field heights were significant for the 1989 and 1992 series, and their corresponding genetic correlations ranged from low to medium (from 0.37 to 0.74). Because of heavy noncrop competition, height growth in the 1991 nursery series showed consistently lower heritabilities and correlations with field performance compared with those of the other two series. Early nursery selection by theoretical prediction was generally efficient for the 1989 and 1992 series. Rank classification analysis indicated that application of early nursery selection should be used with caution for identifying elite families but could be used to cull inferior families or clones, apply multiple-stage selection, or perform positive assortative mating.
Classifying Patterns of Understory Vegetation in Mixed-Oak Forests in Two Ecoregions of Pennsylvania
Authors: Kaeser Melanie J. , Gould Peter J. , McDill Marc E. , Steiner Kim C. , Finley James C. 
Published: August 2019

Abstract
Understory plots in mixed-oak stands in the Ridge and Valley and Allegheny Plateau ecoregions of Pennsylvania were classified to summarize the range of understory conditions common to the region and to evaluate relationships between understory vegetation, overstory conditions, and advance tree regeneration. Factor analysis and cluster analysis were used to identify understory classes. Vegetation cover data including 15 variables (plant species, bare ground, and rocky ground cover) and 4 composite variables (plant species groups) were observed on 1,208 204-m2 plots.The eight vegetation classes resulting from the analyses were associated with different overstory compositions and advance regeneration densities. The understory classes identified in this study may provide insight on the distribution and diversity of problematic and nonproblematic vegetation types.
The Combined Effects of Forest Tent Caterpillar Defoliation and Timber Stand Improvement Activity on Epicormic Sprouting of Sugar Maple and Black Cherry
Authors: Wink Rob A. , Allen Douglas C. 
Published: August 2019

Abstract
A 2 × 2 factorial analysis of variance design assessed the combined effects of severe defoliation by the forest tent caterpillar, Malacosoma disstria (Hub.), from 1991 through 1993 and concurrent timber stand improvement (TSI) treatments on the occurrence of epicormic sproutingfor both sugar maple (SM), Acer saccharum (Marsh.) and black cherry (BC), Prunus serotina (Ehrh.) in the Tug Hill region of New York State. The potential economic effects of epicormic sprouting by dominant and codominant (DC) SM after defoliation and TSI were statistically significantbut negligible. TSI treatments alone and defoliation alone, however, promoted sprouting in intermediate SM, which may result in future grade reduction. The combination of defoliation and TSI treatment resulted in prolific epicormic sprouting by DC BC. These two disturbances have the potential to cause significant standwide value losses in this species.
Frost Crack Incidence in Northern Hardwood Forests of the Southern Boreal–North Temperate Transition Zone
Authors: Burton Julia I. , Zenner Eric K. , Frelich Lee E. 
Published: August 2019

Abstract
Frost cracks are common in northern hardwood stands near their northern range limits. Although they have long been attributed to the regional climate, temperature fluctuations result in surface cracks largely when internal wounds are present. We examined the relationship between the proportion of trees with frost cracks and both tree-level diameter class and stand structural characteristics in primary stands with a history of minimal logging (n = 4) and 67- to 97-year-old second-growth stands subjected to past heavy partial cuts and high grading (n = 8). We hypothesized that frost crack incidence would (1) be greater in the second-growth stands and (2) be associated with differences in structural attributes between the two stand types. High levels of frost cracking in primary stands indicated that cracks are not completely avoidable. However, the proportion of trees with frost cracks was significantly higher in second-growth than primary stands, particularly on small-diameter trees. For example, the odds for frost cracking were 1.66–3.74 times greater in second-growth than in primary stands in the 15-cm diameter class, but were not different in the 45+-cm diameter class. Frost cracking was positively associated with increasing diameter in both stand types. Structural characteristics reflecting tree size, stand basal area, and basal area of hardwoods were positively associated with the proportion of trees with frost cracks in second-growth stands but not in primary stands. Although the basal area of conifers was negatively associated with frost cracking, the effect was likely due to a reduction in hardwood basal area in the vicinity of conifers. We suggest that greater frost crack incidence in second-growth stands is likely a consequence of injuries to residual trees during selective logging.
Foliar Mass and Nutrition of Abies concolor Christmas Trees following Application of Organic and Inorganic Fertilizer
Authors: Slesak Robert A. , Briggs Russell D. 
Published: August 2019

Abstract
Fertilization in Christmas tree production is common to increase tree growth and quality, with many recommendations focusing on N as a primary amendment. However, other nutrients may limit growth, or N application may induce deficiency of other nutrients. We applied fertilizer as either ammonium nitrate (AN) or chicken manure compost (CMC) to concolor fir (Abies concolor [Gord. and Glend.] Lindl.) at eight sites across central New York in 2003 and measured foliar mass and macronutrient response (N, P, K, Ca, and Mg) to assess the potential for an inducible nutrient deficiency or nutrient limitation other than N. Foliage mass, N concentration, and N content increased following both fertilizer treatments, indicating that N limits growth at these sites. Macronutrient (P, K, Mg, Ca) concentrations were reduced following AN application because of nutrient dilution following increased growth. Compared with published sufficiency nutrient concentrations, concentrations of P and K were diluted to levels considered limiting to growth. In contrast, there was no reduction in macronutrient concentrations for P, Ca, and Mg in the CMC application, indicating the potential for this amendment to maintain balanced tree nutrition with increased growth. Foliar K content was increased in the CMC treatment, and needle mass (as the primary growth response variable), was correlated with foliar K concentration (r2 = 0.71, P < 0.01). The results indicate a strong possibility of K limitation in concolor fir across a variety of site conditions. With few exceptions, there were no apparent relationships between soil nutrient pools and foliar nutrition, demonstrating the limitation of soil tests as a guide to nutrient amendments.
Nectria Canker Incidence on Birch (Betula spp.) in Connecticut
Authors: Ward Jeffrey S. , Anagnostakis Sandra , Ferrandino Francis J. 
Published: August 2019

Abstract
A comparison of Nectria canker (caused by Neonectria ditissima) incidence was made between contemporary stands and data sets collected in the 1930s. Cankers were noted on 2,520 black and 1,704 yellow birch growing in 31 study areas used during seven separate surveys in Connecticutbetween 1995 and 2005. Canker incidence was compared with a survey of 6,938 black and 4,117 yellow birch completed during 1934‐1935. Canker incidence in the mid-1930s was much greater than recent incidence for most diameter, crown, and age classes. Birch that grew in open conditionshad higher canker incidence than understory birch. In unmanaged mature stands, canker incidence in 2000 was higher for birch older than 90 years (24%) than for birch 20‐29 years old (1%) and 30‐49 years old (2%). Because the younger birch are probably progeny of intermingled older birch with cankers, is unlikely that the lower incidence of cankers observed on the younger birch was related to local soil conditions, a genetically resistant population, or lack of inoculum. Incidence in more recent surveys was much higher for 20‐29-year-old (12%) and 30‐49-year-old(32%) birch in clearcuts <50 years old than for birch of similar ages in unmanaged forests. Canker incidence of birch in clearcuts was similar to older birch in mature stands and birch during the mid-1930s (13%) that became established following clearcutting or farm abandonment. Canker incidence in birch might be reduced by regeneration prescriptions that minimize exposure of birch saplings to “open-field” environmental conditions during early stand development and by removing infected stems during the early thinning operations.