bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer Corner: Forester's Yield Curve Designer Software
Authors: MacLean David A. , Porter Kevin B. , Kerr Jeff
Published: August 2019

The Forester's Yield Curve Designer(FYCD) software is aimed at helping forest management planners and field foresters in the development and validation of timber volume yield curves. It uses a mouse-driven graphical user interface that facilitates the import and display of results from stand growth models, the comparison of potential curves with permanent sample plot data, and the creation of new curves by drawing, adjusting, and combining curves. FYCD addresses the problem of getting management plan volume yield curve information out to field foresters for validation against available data and experience, and facilitating feedback from the forester to the planner. FYCD also increases the usability of valuable data from permanent and temporary sample plots by allowing easy access and display. This paper describes the primary functionality of FYCD, the data formats used, and how to obtain this free software from the Canadian Forest Service. North. J. Appl. For. 15(1):23-27.
Evaluating Changes in Yellow-Poplar Management in Response to New Low-End Markets
Authors: Pelkki Matthew H. , Arthaud Greg J.
Published: August 2019

Optimal rotation length and thinning schedules for yellow-poplar were determined through the use of a dynamic programming simulation system. Economic and management responses to changing low-end markets for roundwood yellow-poplar were investigated as well as sensitivity to real price increases, interest rates, and number of allowed thinnings in a rotation. It was found that strong markets for low quality and small diameter yellow-poplar shorten rotation lengths and shift low-quality sawtimber into the roundwood markets. In all cases, improvement thinnings were shown to be a valuable thinning strategy and, in many cases, improvement thinning combined with a thinning from above produced the highest financial returns. North. J. Appl. For. 15(1):37-42.
Response of Black Spruce to Thinning and Fertilization in a Drained Swamp
Authors: Hillman Graham R. , Takyi Sam K.
Published: August 2019

A split-plot design experiment replicated in four blocks was established to determine the effects of thinning (main plots) and fertilization (subplots) on growth of a 50- to 60-yr-old stagnant stand of black spruce on a shallow peatland (swamp) in Alberta drained in the previous year in a large-scale experimental project to convert it to a future merchantable stand. The thinning treatments were selective hand-spacing to 1600 trees ha-1 and no thinning. The hand-broadcast fertilizer treatments were: no fertilizer, nitrogen (N), phosphorus (P), potassium (K), NP, PK, NK, and NPK. Nitrogen as NH4NO3 was applied at 200 kg ha-1, P as triplesuperphosphate at 100 kg ha-1, and K as potassium chloride at 100 kg ha-1. After six growing seasons, diameter at breast height, basal area, and volume growth were significantly greater in the thinned treatment than for the same number of large (dominant and codominant) trees in the unthinned treatment. Thinning had no significant effect on height growth. Nitrogen significantly increased dbh, height, basal area, and volume growth, and NP increased the basal area and volume growth. P, K, and PK treatments showed little effects on growth, and P applied alone tended to reduce growth. The results indicated it will be beneficial to supplement drainage with thinning or fertilization with N and N-containing fertilizers or with both shortly after drainage, particularly when other researchers have indicated black spruce may take several years to respond to drainage. North. J. Appl. For. 15(2):98-105.
A Survey to Evaluate Crown Condition of Forest, Roadside, and Urban Maple Trees in Ontario, 1987-1995
Authors: Hopkin Anthony A. , Howse Gordon M.
Published: August 2019

Surveys of sugar maple trees, conducted in Ontario between 1987 and 1995, showed a general improvement in crown condition after 1990. Plots on the shallow soils of the Precambrian shield in central Ontario showed the highest levels of crown dieback in all years. This area was also defoliated at moderate-to-severe levels in 1988. Dieback levels on undefoliated plots were high in 1987-1988, but plots improved after 1988. Defoliated plots showed no improvement, and dieback remained high through 1995. Crown dieback was lower in forest and urban situations than at roadside plots. Roadside plots showed high levels of dieback and should be considered poor indicators of forest condition. Pest damage was recorded on all plot types. Sugar maple in both urban and roadside locations had a higher incidence of stem defects, stem canker, and stem insect damage than trees in forest plots. Root rots were most prevalent at roadside locations. Stem cankers, stem defects, and root rot were most common in the northern forest plots. North. J. Appl. For. 15(3): 141-145.
Site Index of Balsam Poplar/Western Black Cottonwood in Interior and Southcentral Alaska
Authors: Shaw John D. , Packee Edmond C.
Published: August 2019

Stem analysis data were obtained from 268 balsam poplar (Populus balsamifera L.) and black cottonwood (P. trichocarpa Torr. & Gray) trees on 67 sites in interior and southcentral Alaska during 1988-1990 for the purpose of height and volume growth analysis. A modified form of the Chapman-Richards growth model was used to produce polymorphic site index curves. Wide variations in curve shape, which were evident in region-to-region comparisons, required stratification of the data. Site index curves for balsam poplar north of the Alaska Range were produced using one equation and data from 35 sites. The remaining 32 sites, located south of the Range, were divided by landform (fluvial vs. upland). Sites on the middle and upper Susitna and Chulitna Rivers were placed in a separate fluvial class, giving three equations for sites south of the Range. The four equations produce the first polymorphic site index curves for poplars in Alaska. North. J. Appl. For. 15(4):174-181.
Regeneration of Northern Red Oak in Relation to Ectomycorrhizae in Oak and Pine Stands after Overstory and Understory Manipulations
Authors: Zhou Minyi , Sharik Terry L. , Jurgensen Martin F. , Richter Dana L. , Gale Margaret R. , Drummer Thomas D.
Published: August 2019

Growth of northern red oak (Quercus rubra L.) seedlings in relation to colonization by indigenous ectomycorrhizal (ECM) fungi was studied in oak and pine stands in northern Lower Michigan that were subjected to overstory and understory manipulations. Two stand types (oak and pine), three blocks of each stand type, four canopy cover treatments (clearcut, 25% cover (50% cover in the first year), 75% cover and uncut), and two understory treatments (shrub removal and untreated control) were involved in the experiment. Northern red oak acorns from a common seed source were sown in May 1991 to simulate natural regeneration. Seedling growth and its relation to percent ECM were evaluated for the first two growing seasons.

A significantly larger root-collar diameter of northern red oak seedlings was found in pine stands than in oak stands for the first growing season (P < 0.001). However, this difference could not be explained by overall ECM colonization. Seedling growth and ECM colonization were not affected by the shrub removal treatment during the first two growing seasons. In contrast, northern red oak seedling size and weight were strongly influenced by the overstory treatment, with lower levels of canopy cover resulting in larger seedlings. Seedlings had the greatest percent ECM in the partial cover treatment (25-50%) and the lowest percent ECM in the clearcut. After accounting for the effects of canopy cover, the relationship between total biomass of northern red oak seedlings and percent ECM was positively correlated (P = 0.001) during the first growing season and negatively correlated (P = 0.038) during the second growing season. A positive relationship between root/shoot ratio and percent ECM also existed in the first year (P = 0.003) in both oak and pine stands, but only in the oak stands in the second year (P = 0.039). These results indicate that ECM promoted more root development than shoot development, particularly underpartial canopy cover (25%-50%) treatments, where the greatest percent ECM and largest root/shoot ratio were found. Moreover, our results suggest that these partial canopy cover treatments provide a favorable balance between ECM abundance and northern red oak seedling development in both oak and pine stands on intermediate quality sites, and may lead to northern red oak regeneration success on such sites. North. J. Appl. For. 15(4):182-190.
Growth Trends and Management Implications for West Virginia's Red Spruce Forests
Authors: Hornbeck James W. , Kochenderfer James N.
Published: August 2019

Growth trends determined from tree rings are reported for red spruce in three mature stands and three plantations in West Virginia. Annual growth rates in mature forests have stabilized after a period of decline that began around 1960 and lasted for 20-25 yr. Annual growth rates in plantations established between 1935 and 1942 show a gradual decline that can be reversed by thinning. Growth rates and stand basal areas suggest that red spruce forests in West Virginia are healthy and can be highly productive. Management options for expanding the area of red spruce forests include harvesting to encourage or release regeneration, and establishment by planting. North. J. Appl. For. 15(4):197-202.
Sugar Maple Height-Diameter and Age-Diameter Relationships in an Uneven-Aged Northern Hardwood Stand
Authors: Kenefic Laura S. , Nyland Ralph D.
Published: August 2019

Sugar maple (Acer saccharum Marsh.) height-diameter and age-diameter relationships are explored in a balanced uneven-aged northern hardwood stand in central New York. Results show that although both height and age vary considerably with diameter, these relationships can be described by statistically valid equations. The age-diameter relationship compares favorably to one reported by Tubbs (1977) for sugar maple in unmanaged (virgin) northern hardwoods, suggesting that periodic cuttings improved growing conditions in our stand. Deliberate attempts to control size-class distribution and tree spacing should continue to increase diameter growth rates and decrease the time needed to reach certain threshold tree sizes. Growth rates that can be reasonably expected in this and similarly structured stands are provided. Lastly, a wide range of heights and diameters are documented, confirming the structural complexity associated with the balanced selection system. An equation to predict sugar maple height from diameter is provided and may prove useful when assessing habitat or visual characteristics of complex uneven-aged stands. North. J. Appl. For. 16(1):43-47.
Response of Immature Trembling Aspen to Season and Height of Cut
Authors: Bell F. Wayne , Pitt Douglas G. , Morneault Andrée E. , Pickering Susan M.
Published: August 2019

Forest managers in Ontario have identified trembling aspen (Populus tremuloides Michx.) as the most significant competitor of our commercially important spruce and pine crop. Although herbicides can be used to effectively control aspen, the public of Ontario would prefer to have herbicide alternatives, such as motor-manual cutting, used on public lands. Cutting of aspen has not been very successful, and research is required to improve its effectiveness. Effects of season and height of cutting to control the regrowth of young trembling aspen were studied on four sites in Ontario,Canada, with each location providing a replicate for the trial. Aspen stems, averaging 1.5 to 3.2 m in height, were cut in fall (October 1993), winter (February/March 1994), and summer (June/July 1994) at 10, 25, 50, 75, or 100 cm above ground level. Density and height of new root suckers;number, point of origin, and growth of stem sprouts; and tissue mortality in cut stems were evaluated by analyses of variance with linear contrasts to determine the effects of cutting height, season of cutting, and their interactions. Two years of post-treatment data indicate that aspen regeneration may be reduced if manual cutting occurs in June/July, at a cutting height of 50 to 75 cm. This timing and cutting height provides maximum stem mortality with minimum number of sprouts per stem and minimum sucker regeneration. If aspen regeneration is the goal, cut in the fall at 25 cm for maximum regrowth. North. J. Appl. For. 16(2):108-114.
Stand Structure in Evenaged Northern Hardwoods: Development and Silvicultural Implications
Authors: Leak William B.
Published: August 2019

Stand structure was examined in evenaged northern hardwoods in New Hampshire in terms of diameter distribution (numbers of trees by dbh class) and spatial distribution of basal area by species. Diameter distributions by species and for all species combined were graphed for stands varying in age class from 7-9 yr up to 60-68 yr. Over time, these northern hardwood stands develop a layered canopy structure with the intolerant and short-lived paper birch and aspen dominating the larger size classes and exhibiting a bell-shaped diameter distribution. Longer lived species, most abundant in the smaller size classes, exhibit flat or very skewed bell-shaped distributions. The usual silvicultural recommendation in such stands is to thin to prescribed stocking levels, leaving adequate stocking in larger stems of the longer lived species and gradually removing the intolerants as they reach maturity. However, appreciable spatial variation in the abundance of aspen-birch and longer lived species may prevent uniform application of this approach; i.e., some areas in certain stands do not have adequate stocking of the longer lived species once the aspen-birch is removed.In variable stands such as this, a gradual transition to group selection may be a better tactic. North. J. Appl. For. 16(2):115-119.
Determinants of Land Use in Maine with Projections to 2050
Authors: Mauldin Thomas E. , Plantinga Andrew J. , Alig Ralph J.
Published: August 2019

Data on land use in Maine are assembled from USDA Forest Service inventories, the Census of Agriculture, and other sources. Regression analysis is used to estimate the relationships between land use and determinants of land use such as land rents and soil characteristics. The fitted models are used to project changes in land use to 2050. We project declines in private timberland area, though these losses are small on a percentage basis. Continued declines in agricultural land area and increases in urban land area also are projected. Land use policies that influence land rents such as preferential tax assessment programs can be used to deter socially undesirable land use changes. North. J. Appl. For. 16(2):82-88.
Species Composition and Structure of a Northern Hardwood Stand After 61 Years of Group/Patch Selection
Authors: Leak W. B.
Published: August 2019

The 61-year results from a study of group/patch selection in New Hampshire (four entries, 0.5 ac average opening size) showed that this system will maintain a continued proportion of about 20% of the basal area in bitches and ash, or about one-third in all intolerant/intermediate species.The diameter distribution closely followed the J-shaped curve typical of unevenaged forests. There was a dead standing component of about 20 trees per acre including 3 sawtimber-sized stems. North. J. Appl. For: 16(3):151-153.
Assessing Scarcity of the North Central Veneer Log Resource
Authors: McGuire Mike , Stevens James , Potter-Witter Karen
Published: August 2019

Forest industry professionals have expressed concern about physical scarcity and diminishing quality in veneer logs of the preferred species, contradicting USDA Forest Service inventory results that report an expanding resource base. This study examined factors, influencing economic supply of select white oak, select red oak, hard maple, ash, black cherry, and black walnut veneer logs in the Lake States, Illinois, and Indiana. Increased competition due to international demand is placing additional pressure on available inventory. Changing demographics are acting to reduce supply as nontimber land uses increase in importance. Industry professionals were queried to quantify their perception of scarcity and determine which factors they consider most important. The dominant perception is that quality is decreasing. Profitable architectural and panel grade veneer logs are perceived to be diminishing while furniture grade veneer logs are not. Quantity is perceived to be decreasing in the large and medium diameter classes but increasing in the small diameter classes. Expectation is for future real prices 10 yr hence to increase between 20-30%. Factors for the perceived scarcity ranking highest in importance were increased international demand, previous high grading, landowner mistrust of loggers, and increased environmental regulations. Respondents agreed that the world demand for eastern hardwoods is strong and will continue to grow. North.J. Appl. For. 16(3):160-166.
Assessing Application and Effectiveness of Forestry Best Management Practices in New York
Authors: Schuler Jamie L. , Briggs Russel D.
Published: August 2019

Forty-two forestry best management practices (BMPs) were assessed to determine the extent of voluntary application and their effectiveness in preventing water quality impacts in New York State. These BMPs were evaluated on 61 timber-harvested sites in the Catskill region (CR), and 53 timber harvested sites in the Adirondack region (AR) during the summers of 1997 and 1998. The overall application of suggested BMPs was 78% for haul roads, 87% for landings, 59% for skid trails, 88% for equipment maintenance/operation, and 73% for buffer strips. Departures were common for BMPs concerned with draining water off haul roads and skid trails, and for stream crossings; more attention must be devoted to those practices. Effectiveness of BMPs was apparent when they were applied. Nonparametric statistical tests showed a strong relationship between BMP application and prevention of sediment movement. Limiting sediment movement protects surface water. In the CR, 27 of the 33 BMPs tested showed a statistically significant (P < 0.10) relationship between BMP application and sediment movement. Similar results were observed in the AR; 26 of the BMPs tested were significantly associated with sediment movement. Imperfect application of BMPs reduced effectiveness. Road drainage structures, for example, generally failed to adequately control erosion when spacing between drainage structures was excessive. North. J. Appl. For. 17(4): 125–134.
Heavy Grazing of Canadian Bluejoint to Enhance Hardwood and White Spruce Regeneration
Authors: Collins William B.
Published: August 2019

Wet, disclimax stands of Canadian bluejoint (Calamagrostis canadensis [Michx.] Beauv.) created by logging were heavily grazed by cattle and horses years 5 through 8 after logging to weaken the grass and favor regeneration of hardwoods and white spruce (Picea glauca [Moench.] Voss). Seedling densities of hardwoods and white spruce in heavily grazed stands were not significantly different (P < 0.05) from those in ungrazed stands. Heavy grazing reduced herbaceous cover and litter but was not detrimental to runoff water quality. Heavy grazing was not effective for increasing regeneration in wet disclimax stands of Canadian bluejoint where the grass had already increased following overstory removal, but earlier application and use in drier sites should be considered. North. J. Appl. For. 18(1):19–21.
Field Note: Observations on Planted Black Walnut in Vermont
Authors: Heitzman Mark
Published: August 2019

A favorable 8 yr experience growing black walnut utilizing tree shelters in northern New England is described. North. J. Appl. For. 18(2):44–45.
Fuel Model Selection for BEHAVE in Midwestern Oak Savannas
Authors: Grabner Keith W. , Dwyer John P. , Cutter Bruce E.
Published: August 2019

BEHAVE, a fire behavior prediction system, can be a useful tool for managing areas with prescribed fire. However, the proper choice of fuel models can be critical in developing management scenarios. BEHAVE predictions were evaluated using four standardized fuel models that partially described oak savanna fuel conditions: Fuel Model 1 (Short Grass), 2 (Timber and Grass), 3 (Tall Grass), and 9 (Hardwood Litter). Although all four models yielded regressions with R2 in excess of 0.8, Fuel Model 2 produced the most reliable fire behavior predictions. North. J. Appl. For. 18(3):74–80.
Incidence of Annual Canker of Sugar Maple Studied with the Aid of a Geographic Information System
Authors: Bergdahl Dale R. , Sendak Paul E. , Tobi Donald R. , Bove James R. , Tritton Louise M.
Published: August 2019

Sugar maples (Acer saccharum Marsh) ≥ 2.0 in. dbh were evaluated for incidence of annual canker caused by Fusarium spp. A total of 1,880 trees were evaluated from 73 plots located on 635 ac of privately owned northern hardwood forest in north central Vermont. About 12% of the trees were dead and one-fourth of both living and dead trees had annual canker. A logistic regression model was used to assess the role of soil-site characteristics related to the incidence of annual cankering. Probability estimates from the estimated regression equation were used to generate a map of annual canker risk. The generality of the results obtained here are untested and need to be applied to a more extensive area for validation. However, the technique for forest disease risk assessment could have wide application. We found annual canker was more common on sites that maintained a high number of stems per acre, on sites that were shallow to bedrock, and on sites that were dominated by sugar maple. We believe these findings suggest that sites that have shallow soils that include sugar maple probably should not be managed to encourage sugar maple. Sugar maple probably should be managed in stands that contain ample stocking of other northern hardwood species, and cultural practices that encourage maple over other species probably should be avoided.
Evaluation of Four Herbicides and Tillage for Weed Control on 1-0 Planted Tree Seedlings
Authors: Seifert John R. , Woeste Keith
Published: August 2019

Azafenidin, sulfometuron, pendimethalin, and simazine were applied alone and in combination to 1-0 seedlings of nine hardwood and one conifer species. Percent bare ground at 30, 60, and 90 days, diameter and height growth of the seedlings were determined for 16 herbicide treatments, tillage and a control. Azafenidin applications alone and in combination with sulfometuron resulted in about 85% bare ground 90 days post-treatment. There were significant differences for diameter, height growth, and volume among the treatments for every species. No single treatment ranked best for all species, but comparison of the mean ranks of the treatments for all species indicated that azafenidin and pendimethalin resulted in the most growth. Azafenidin-treated seedlings also had the greatest volume at the end of the season.
State Survey of Silviculture Nonpoint Source Programs: A Comparison of the 2000 Northeastern and National Results
Authors: Edwards Pamela J. , Stuart Gordon W.
Published: August 2019

The National Association of State Foresters conducts surveys of silviculture nonpoint source (NPS) pollution control programs to measure progress and identify needs. The 2000 survey results are summarized here for the nation and for the 20-state northeastern region. Current emphasis of NPS pollution programs is on education, training, and monitoring. Educational efforts are used to make more landowners aware of their responsibilities to control pollution during timber harvesting and to make the public and lawmakers more aware of effective pollution control procedures for forestry. Training of foresters, loggers, and landowners in NPS pollution control expanded during the last 4 yr in part due to forest industry's Sustainable Forest Initiative and increased logger accreditation and forester licensing programs. Several states reported improved compliance and performance in controlling NPS pollution as a result of certification and licensing programs. Recommendations are made to continue the progress in NPS pollution control in forestry.
Germination Percentage and Germination Speed of European Larch (Larix decidua Mill.) Seed After Prolonged Storage
Authors: David Andrew
Published: August 2019

Thirty European larch seedlots stored in plastic, screw-capped containers at 4°C for 3 to 24 yr were tested for their viability. The average germination percentage was 26.7% per seedlot. Fifty percent of all germinating seeds germinated by the 20th day after sowing and 90% had germinated by the 26th day. Correlation analysis indicated there was a significant negative association between years in storage and germination percentage and a significant positive association between years of storage and the number of days required to reach 15% germination. Although one seedlot germinated no seeds after 10 yr in storage, 21 of 30 seedlots, ranging from 3 to 24 yr in storage, maintained a minimum germination percentage of 20%.
Raven Damage to Plastic Seeding Shelters in Interior Alaska
Authors: Putman William E. , Zasada John C.
Published: August 2019

Two types of plastic seeding shelters are being tested in interior Alaska for regenerating white spruce. Raven damage to shelters has been observed on sites seeded shortly after burning. Damage averaged 68% with cones and 50% with funnels on a burned upland site, and 26% with funnels on a burned floodplain site. Damage was highly variable and appeared to be related to time of sowing and vegetation development near the seedspots. Care should be taken when considering use of seeding shelters after burning.

North J. Appl. For. 2:41-43, June 1985.
Effects of Cold Storage and Planting Date on Red Pine Survival and Growth
Authors: Emch Dallas J. , Carvell Kenneth L.
Published: August 2019

Effects of cold storage and planting date on first-year survival and height growth of red pine seedlings were evaluated in a one-year study in north-central West Virginia. Both survival and height growth were reduced as time in cold storage increased. Good survival was obtained for plantings made as late as 25 June, after 73 days in cold storage. Satisfactory height growth occurred for plantings made as late as 23 July. There was no significant difference in survival before and after fall frost for any planting dates except the 20 August planting. Reduced height growth for the later plantings was probably a consequence of the short growing season remaining. There was no indication that the length of time in cold storage affected the period required for buds to break dormancy.

North J. Appl. For. 2:51-53, June 1985.
Ponderosa Pine Provenance Test for Windbreaks in Eastern South Dakota
Authors: Schaefer Peter R. , Baer Norman W.
Published: August 2019

Ponderosa pine has been planted extensively in the northern Great Plains. Many of the plantings, however, have performed poorly or failed because of poor early survival and slow growth. A regional provenance test of 73 ponderosa pine sources was established in 1968 as one means of improving the performance of this species throughout the Great Plains. Results after 15 years indicated that three sources located in north central Nebraska and south central South Dakota were taller than all other sources. The three sources exhibited a height growth 30% above the plantation mean and an average survival 20% higher than that of the plantation as a whole. These sources have also been among the tallest and best survivors in similar tests throughout the Great Plains. Juvenile-mature correlations were strong for 5-year and 15-year height growth. The identification of a relatively small area from which to collect genetically improved ponderosa pine should greatly facilitate the incorporation of these seedlings into tree-planting efforts in the northern Plains.

North. J. Appl. For. 2:105-107, Dec. 1985.
STEMS Model Projection Capability with Plot and Tree Data Aggregation
Authors: Ek Alan R. , Randall Bryan L. , Hahn Jerold T. , Buchman Roland G.
Published: August 2019

Projections of forest plot characteristics were made using the STEMS individual-tree based stand growth model for jack pine, red pine, maple-birch and aspen cover types from Michigan, Minnesota, and Wisconsin for periods of up to 50 years. Tree lists were constructed from forest survey records using various plot and tree aggregation methods, then projected and compared to projections of the same data without aggregation. The loss in projection precision due to aggregation was then weighed against savings in computer processing time as compared to the unaggregated projections. Differences between aggregated and unaggregated projections increased with greater aggregation and with longer projection periods, but in most cases were less than 10% at 50 years when the plot data were aggregated by stand density class. The largest differences were observed for pulpwood and sawtimber volumes. However, these differences were in part a function of merchantability limits based on tree size. Results indicate that dramatic cost savings can be realized with little loss in precision.

North. J. Appl. For. 2:121-127, Dec. 1985.
To Thin or Not to Thin: Using the Forest Vegetation Simulator to Evaluate Thinning of Aspen
Authors: Gilmore Daniel W.
Published: August 2019

Thinning experiments are costly to install and take decades of monitoring. Computer simulation tools, however, allow for the creation of “virtual” thinning experiments that forest managers can use as a guide in prescribing thinnings. The Forest Vegetation Simulator (FVS) was used to conduct a “virtual” thinning experiment to a range of residual densities (8, 10, 12, 15, and 20 ft spacings) at a range of thinning ages (5, 10, 25, and 40 yr) over a 50 yr time period. Stand level volume production was not enhanced through precommercial thinning, but average tree diameter was increased. Stand level volume was less after commercial thinnings but total volume production was increased if volumes removed during thinnings were considered. Tree diameter growth was greater when thinnings were performed at a younger age at and at a wider spacing. The greatest total volume production (removed during thinning and standing at age 50) was found to be nearly equal at 8 ft and 10 ft spacing with thinnings occurring at ages 10 or 25 on a site index of 80. North. J. Appl. For. 20(1):14–18.
Effect of Method of Thinning on Wood Production in a Red Pine Plantation
Authors: Smith David M.
Published: August 2019

The total production of main-stem wood volume by a red pine plantation in New Hampshire did not differ during a 12 yr period between (a) low, (b) crown, and (c) selection thinning when the same amount of basal area was reserved in two successive thinnings. The reservation of larger trees in low and crown thinning improved production of board-foot volume and such trees suffered less mortality from annosus root disease. North. J. Appl. For. 20(1):39–42.
Germination and Survival of Spruce Seedlings Following Fire in Northwestern Alberta
Authors: Berger Carrie A. , Gilmore Daniel W
Published: August 2019

Thirty semipermanent plots were established in a 10 ha (24.7 ac) spruce stand the spring following a winter harvest and subsequent prescribed burn to monitor germination by month and overwinter survival of spruce seedlings. Seventy percent of all germination occurred in June with regeneration densities as high as 800,000 germinants ha-1 (323,755 ac-1). Most germination occurred, and overwinter survival was highest in depressed microsites. Overwinter survival averaged 68,000 seedlings ha-1 (27,520 ac-1), with June germinants having greater survival then July or August germinants. Only three new germinants were detected the second spring following the prescribed burn. North. J. Appl. For. 20(1):45–47.
Extreme Weather and Forest Management in the Mid-Atlantic Region of the United States
Authors: DeWalle David R. , Buda Anthony R. , Fisher Ann
Published: August 2019

Projected climate change could have major effects on forest management because of the potential for increased frequency, duration, and/or severity of extreme weather events. We surveyed public and private forestland management groups in the Mid-Atlantic region of the United States to better understand current interactions between extreme weather events and forest land management and to help predict future impacts. Our questionnaire addressed the importance and types of problems created by extreme weather events, the coping strategies employed to mitigate problems, and the overall economic effects of extreme weather. Responses were received from 322 forest managers/users (54% response rate) primarily representing state natural resources agencies, forestry consulting firms, large industrial forestry companies and smaller logging companies. Overall, respondents rated the impacts of extreme weather on their operations as low to modest; however, over 20% experienced “major” effects because of extreme weather over the past 10 yr. The highest rated impacts were: (1) reduced access to forestland because of flooding, deep snow, or wind- and ice-damaged trees; (2) increased costs for road and facility maintenance, and (3) direct damage to trees by wind, snow, or ice and subsequent effects on timber supplies and market prices. Mitigation strategies most commonly mentioned were switching of silvicultural systems and changing site preparation and planting schemes, but most respondents had not altered their management due to extreme weather. When asked about effects of a hypothetical 25% increase in severe weather, the most common mitigation strategy was increased investment in new equipment and facilities. Short-term economic impacts of severe weather varied between “supply increasing” conditions associated with increased tree damage and salvage operations and “supply decreasing” conditions related to reduced access to forest land. Increased severe weather due to climate change can be expected to have small to modest effects on forest management and users overall, but areas subjected to hurricanes and ice storms within the Mid-Atlantic region appear to be more sensitive to impacts of severe weather. North. J. Appl. For. 20(2):61–70.
Hardwood Stumpage Price Trends and Regional Market Differences in Pennsylvania
Authors: Linehan Peter E. , Jacobson Michael G. , McDill Marc E.
Published: August 2019

Pennsylvania is a major hardwood lumber producing state. Since 1984, the Pennsylvania Timber Market Report (TMR) has provided quarterly stumpage and mill-delivered prices for important timber species groups for four subregions within the state. Stumpage price data covering the period from 1984 to 2000 are available for eight species groups. These series were analyzed with log-linear regression to determine nominal and real price growth rates. While all species show increasing prices over the period, three distinct groups are identified. Black cherry and hard maple show the highest rates of price growth (10.1% to 14.1% nominal and 6.5% to 10.7% real); northern red oak, soft maple, and yellow-poplar form an intermediate group (6.6% to 9.5% nominal and 3.1% to 6.1% real); and white oak, white ash, and miscellaneous hardwoods show the lowest rates of growth (4.3% to 6.8% nominal and 0.0% to 3.6% real). Additionally, a regression model with qualitative regional variables (i.e., “dummy” variables) was used to test whether the four market regions used by the TMR are statistically different, in terms of both the general level of prices and rates of change. The results clearly show significant differences in the price levels and trends among all regions for at least some species groups. The two regions showing the fewest significant differences are the southeast and southwest regions. The two northern regions are quite different from the southern regions. The northwest region was the most distinct of all the regions. Specific regional differences are noted for individual species groups. North. J. Appl. For. 20(3):124–130.
Mortality Patterns Following Spruce Budworm Infestation in Unprotected Spruce-Fir Forests in Maine
Authors: Solomon Dale S. , Zhang Lianjun , Brann Thomas B. , Larrick David S.
Published: August 2019

Cumulative and annual mortality of red spruce (Picea rubens Sarg.) and balsam fir [Abies balsamea (L.) Mill.] were examined over a 10 yr period to follow the mortality patterns in unprotected spruce-fir forests in northern Maine. Different mortality patterns were determined based on stand composition classes and merchantability classes. In general, balsam fir was more vulnerable to budworm attack, and reached 92–100% basal area mortality and 84–97% stem density mortality 12 yr after the start of the outbreak. Red spruce, in contrast, had approximately 32–59% basal area mortality and 30–66% stem density mortality during the same time period. Balsam fir mortality started 1 to 2 yr before spruce, while spruce mortality continued 2 to 3 yr after fir mortality was completed. Higher mortality was found in smaller trees than sawtimber-sized trees. Stands with hardwood components (30–70% in basal area) had the lowest mortality rate for both species. Furthermore, Schnute growth function (Schnute 1981) was used to characterize the cumulative mortality trajectories after the defoliation of spruce and fir by stand composition classes. The models estimated the time when annual mortality achieved maximum, the cumulative mortality at that time, and the asymptotic mortality over a long time period after the start of the attack. The information can provide guidelines for predicting protection strategies and scheduling salvage harvests.
Splitting in Fire-Killed Trees in the Boreal Forest of Alberta
Authors: Nakamura Nobutaka , Woodard Paul M. , Bach Lars
Published: August 2019

Tree boles in the boreal forests of Alberta, Canada will split once killed by a stand-replacing crown fire. A total of 1,485 fire-killed trees were sampled, 1 yr after burning, in 23 plots in 14 widely separated stands within a 370,000 ha fire. Sampling occurred in the Upper and Lower Foothills natural subregions. The frequency of splitting varied by species but averaged 41% for all species. The order in the frequency of splitting was balsam fir, black spruce, white spruce and lodgepole pine. The type of splitting (straight, spiral, or multiple) varied by species, as did the position of the split on the tree bole. Aspect or solar angle was not statistically related to the type or occurrence of splitting.
Effects of Selective Forest Harvesting on Organic Matter Inputs and Accumulation in Headwater Streams
Authors: Kreutzweiser David P. , Capell Scott S. , Beall Frederick D.
Published: August 2019

Organic matter inputs and accumulation were measured in streams of low-order forest watersheds across a gradient of selective harvesting with no protective riparian buffers assigned. Comparisons were made among sites in selection-cut (average 29% basal area removal), shelterwood-cut (average 42% basal area removal), diameter limit-cut (average 89% basal area removal), and undisturbed tolerant hardwood catchments. The diameter limit harvest was an intentionally high-disturbance treatment and is not a normal silvicultural prescription for tolerant hardwoods in Ontario. Time trend analyses were conducted to examine differences among sites over a pre- and postharvest experimental period. Selection-based harvesting at up to 42% basal area removal with no riparian buffers did not significantly alter average over-stream canopy cover, leaf litter and other organic matter inputs, benthic particulate organic matter accumulation, or woody debris abundance. Harvesting impacts on over-stream canopy cover and organic matter inputs appeared to be minimized by natural crown architecture (overlap in crowns of over-stream trees, residual mid-crown canopy) and by careful logging practices including retention of many immediate streamside trees (within a few meters of the stream channel) and avoidance of felling directly into the streams. Dissolved organic matter fluxes increased slightly for 1 year after harvest and were associated with increased water yield. At the diameter limit harvesting intensity (about 89% basal area removal), significant effects on organic matter inputs and accumulation in streams were detected. The results indicate that selective harvesting of hardwood forests at up to about 42% basal area removal can be conducted without causing significant reductions in organic matter inputs and accumulation in headwater streams, even without prescribed streamside buffer strips.
An Evaluation of Changes in Tree Crown Characteristics to Assess Forest Health in Two Indiana State Parks
Authors: Randolph KaDonna C. , Moser John W.
Published: August 2019

An evaluation of tree crown characteristics was conducted by means of a Forest Health Monitoring study in Turkey Run and Shades State Parks, Indiana. Crown dieback, foliage transparency, and crown density were summarized for three consecutive measurement years, and the short-term changes in these characteristics were quantified in an effort to identify potential forest health concerns. In both Shades and Turkey Run State Parks, no significant changes were detected in the levels of crown dieback and crown density. Only for Shades hardwoods, and more specifically hickory trees (Carya spp.), was there an unfavorable change in foliage transparency; however, this change did not appear extraordinary given the Forest Health Monitoring measurement quality objectives. This study demonstrated that given the current body of knowledge about the acceptable levels for the crown characteristics, the majority of trees in Shades and Turkey Run State Parks are not exhibiting responses to extreme stress and should be considered healthy.
A GIS Methodology for Generating Riparian Tree Planting Recommendations
Authors: Carver Andrew D. , Danskin Scott D. , Zaczek James J. , Mangun Jean C. , Williard Karl W. J.
Published: August 2019

The purpose of this study was to develop a method for determining optimal planting recommendations for bottomlands and riparian buffer strips within a geographic information system (GIS) framework. The specific objective of this study was the development of a decision support model to generate riparian tree-planting recommendations based on site characteristics. Unlike previous research, this study enhances the usefulness of conventional site evaluation guides by incorporating digital soil surveys and other spatial data at a level of detail and automation previously unavailable. Research was conducted in the Cypress Creek Quadrangle, southern Illinois, and planting recommendations were generated for eight bottomland hardwood species. Model results were consistent with accepted silvicultural recommendations. Species were consistently placed within sites most suitable for each individual's requirements, and as a result, model recommendations should produce riparian forests optimizing growth potential. By adopting this approach, more productive forest cover could be established while concurrently reducing costs associated with on-site evaluations.
Equations for Predicting Merchantable Yield and Diameter Distribution for Lake States Red Pine
Authors: Mack Timothy J. , Burk Thomas E.
Published: August 2019

This article describes the construction and application of a stand-level merchantable yield equation for red pine in the Lake States. The equation predicts merchantable cubic foot volume for the stand based on minimum dbh and top size thresholds defined by the user. The merchantable yield equation can be used to model the merchandizing of user-defined products from stands given total stand volume, quadratic mean dbh, and the number of trees per acre. Also presented is an equation for estimating the distribution of trees per acre within a stand by dbh class. The equation predicts number of trees per acre larger than a specified dbh given the surviving number of trees per acre and mean dbh. The trees per acre equation can be used to describe the distribution of both diameter and basal area given number of trees per acre and quadratic mean dbh.
Growth and Injury Patterns of Eastern White Pine (Pinus strobus L.) Seedlings as Affected by Hardwood Overstory Density and Weeding Treatments
Authors: Krueger Jerome A. , Puettmann Klaus J.
Published: August 2019

White pine seedlings were underplanted under a range of overstory densities in a hardwood stand in northern Minnesota. Vegetation surrounding seedlings was left untreated (control), weeded annually, or completely removed through monthly weeding. After 4 years, the benefit of weeding woody competition for diameter growth of seedlings was limited to areas with relatively open overstory conditions. Seedling height growth was reduced in areas with higher overstory density, but improved through weeding treatments that removed woody vegetation. The removal of herbaceous vegetation did not improve growth of seedlings in any conditions. Open growing conditions created by overstory removal and weed control resulted in higher incidences of seedling injuries, e.g., through infection by white pine blister rust. Conditions for pine bark adelgids also were enhanced in areas with low overstory densities and weeding treatments. The incidence for white pine weevil seems to follow a similar pattern, although the number of trees infected was minimal. Results show that improving growing conditions through management of the overstory and understory vegetation improves seedling growth rates, but must be balanced with potentially higher incidences of seedling injuries under more open conditions.
Use of an Aspen Overstory to Control Understory Herbaceous Species, Bluejoint Grass (Calamagrostis canadensis), and Fireweed (Epilobium angustifolium)
Authors: Maundrell Chris , Hawkins Chris
Published: August 2019

To enhance white spruce [Picea glauca (Moench) Voss] regeneration and growth, the potential for using an aspen (Populus tremuloides Michx.) overstory to suppress bluejoint grass [Calamagrostis canadensis (Michx.)] and fireweed (Epilobium angustifolium L) was investigated. Response to canopy opening was assessed on 10 treatments where the canopy had been incrementally opened. At the summer solstice, measurements of attenuated light were taken at 1.3 meters (breast height). Bluejoint grass and fireweed both responded with greater ground cover as the photosynthetic photon flux density increased (R2 = 0.84, P = 0.0002; R2 = 0.90, P = 0.0001; respectively). Where aspen has developed an overstory canopy, it may be possible to control competing vegetation to create favorable environmental conditions for spruce re-establishment, growth, and release while encouraging a sustainable mixedwood stand.
Efficient Sampling Grids for Timber Cruises
Authors: Brooks John R. , Wiant Harry V.
Published: August 2019

Equations are provided to permit forest inventory specialists to quantitatively estimate the total field inventory travel distance, and thus time, based solely on inputs of property size, the number of inventory samples desired, and the type of systematic grid employed. Total inventorytravel time is estimated for square and varying rectangular grid spacings for property sizes from 100 to 10,000 ac to estimate the time savings for rectangular grids over square grid patterns for the same number of inventory samples.