Central Hardwood Research Articles

A Decrease in Oak Litter Mass Changes Nutrient Dynamics in the Litter Layer of a Central Hardwood Forest

Abstract The abundance of oak is declining in the central hardwood forest, resulting in structural and functional changes in the litter layer. We hypothesized that a decline in oak litter mass associated with a lower oak component will result in an increase in nutrient cycling rates in the litterlayer. To test this hypothesis, we compared mass loss and C, N, P, and Ca dynamics in pure oak litter and in litter made of 48% oak plus 52% five other deciduous species in a central hardwood forest in West Virginia. In 12 months of litter decomposition, pure oak litter decomposed more slowly,retained more C and N, immobilized more and subsequently did not release P, and released less Ca than litter consisting of 48% oak plus five other species. Annual stand-level nutrient fluxes in pure oak and in 48% oak plus five other species litter were correspondingly +4.1 and −4.4kg ha−1 N, +0.22 and −0.17 kg ha−1 P, and −9.3 and −16.7 kg ha−1 Ca. These results indicate that a decline in oak will cause more rapid nutrient cycling in the litter layer of affected central hardwood stands.

Fire History of a Rimrock Pine Forest at New River Gorge National River, West Virginia

The fire history of a rimrock pine forest at the New River Gorge National River, West Virginia, was studied using 21 fire-scarred Pinus virginiana Mill. (Virginia pine) cross-sections. Fire frequency and the goodness-of-fit between the fire interval distribution and the normal and Weibull distributions were evaluated with the FHX2® program. A 107-year fire chronology (1898–2005) was constructed from 53 fire scars. Fire intervals ranged from 1 to 8 years. The Weibull median interval was approximately 3 years using liberal (one or more trees scarred during a single year) or conservative (two or more trees scarred during a single year) criteria. Similar to other mixed forest stands in the Central Hardwood Region, fires in the 20th century were likely ignited from coal mining activities and steam-driven locomotives near the study site. Anthropogenic fires may have caused an artificial increase in rimrock pine forests or allowed pines to persist in greater numbers than would be possible in the absence of disturbance. Restoration (e.g., prescribed burning) is probably not needed to retain P. virginiana as a component of the rimrock forest, but the species' dominance will continue to be restricted on the rim of the gorge.

Assessing Ecoregional‐Scale Habitat Suitability Index Models for Priority Landbirds

ABSTRACT Emerging methods in habitat and wildlife population modeling promise new horizons in conservation but only if these methods provide robust population‐habitat linkages. We used Breeding Bird Survey (BBS) data to verify and validate newly developed habitat suitability index (HSI) models for 40 priority landbird species in the Central Hardwoods and West Gulf Coastal Plain/Ouachitas Bird Conservation Regions. We considered a species’ HSI model verified if there was a significant rank correlation between mean predicted HSI score and mean observed BBS abundance across the 88 ecological subsections within these Bird Conservation Regions. When we included all subsections, correlations verified 37 models. Models for 3 species were unverified. Rank correlations for an additional 5 species were not significant when analyses included only subsections with BBS abundance >0. To validate models, we developed generalized linear models with mean observed BBS abundance as the response variable and mean HSI score and Bird Conservation Region as predictor variables. We considered verified models validated if the overall model was an improvement over an intercept‐only null model and the coefficient on the HSI variable in the model was >0. Validation provided a more rigorous assessment of model performance than verification, and models for 12 species that we verified failed validation. Species whose models failed validation were either poorly sampled by BBS protocols or associated with woodland and shrubland habitats embedded within predominantly open landscapes. We validated models for 25 species. Habitat specialists and species reaching their highest densities in predominantly forested landscapes were more likely to have validated models. In their current form, validated models are useful for conservation planning of priority landbirds and offer both insight into limiting factors at ecoregional scales and a framework for monitoring priority landbird populations from readily available national data sets.

Competitive interaction between Microstegium vimineum and first-year seedlings of three central hardwoods1

Abstract We established an experiment designed to compare effects of Microstegium vimineum (Japanese stiltgrass) on seedlings of three native hardwood species to investigate the hypothesis that competitive effects of M. vimineum on juvenile trees will vary across different tree species. Growth and survival of Acer rubrum, Liriodendron tulipifera, and Quercus rubra first-year seedlings were compared in plots with and without M. vimineum in three planting beds under 50 percent shade. The tree species studied are abundant and of particular interest in the Central Hardwood Region. A. rubrum and L. tulipifera seedlings experienced reduced growth in several foliar characteristics in the presence of M. vimineum. Q. rubra did not exhibit any differences in foliar characteristics between plots with and without M. vimineum, however there was a reduction in Q. rubra stem weight as a result of the presence of M. vimineum. The differential responses of A. rubrum, L. tulipifera, and Q. rubra to the presence of M. vimin...

Oak Ecosystem Management Considerations for Central Hardwoods Stands Arising from Silvicultural Clearcutting

Abstract Silvicultural clearcutting was widely used during the late 20th century to regenerate stands on upland sites and achieve timber production objectives within the central hardwood region. As these even-aged stands develop, silvicultural guidelines are needed to address newer management objectives emphasizing oak ecosystem maintenance. The US Forest Service Common Stand Exam procedure (Common Stand Exam Users Guide, 2003, Ver. 1.5.1, US Forest Service, Washington, DC, 87 p.) was modified to assess stand stocking, composition, oak (Quercus) competitive status, and other emerging management concerns. A total of 74 randomly selected upland stands that had been silviculturally clearcut between 1980 and 1990 were sampled across the Shawnee National Forest in southern Illinois. Maples (Acer spp.) and yellow-poplar (Liriodendron tulipifera L.) predominated across all landscape positions 15–26 years after stand initiation. Oak (Quercus spp.) trees per acre was related to landscape position and averaged less than 50 trees/ac on the more productive lower slope positions and north aspects. However, when yellow-poplar was present, oaks were in a competitively inferior canopy position regardless of slope position or aspect. Our results show that for sustaining oak ecosystems in this region, management interventions favoring oaks should focus on the most productive sites, where crop tree release would reduce yellow-poplar interference with a sparse oak resource, as well as on less productive sites, where thinning to reduce stocking may be needed to maintain stand health.

Effects of Microsites Created by Selective Harvesting on Growth of Microstegium vimineum in a Central Hardwood Forest

Abstract Disturbances related to silvicultural activities are inevitable and may facilitate the spread of established populations of exotic species. Microstegium vimineum is an annual exotic grass that has spread throughout the eastern United States. Different categories of understory microsites resulting from cutting and the operation of logging machines within three selective harvest units were identified and characterized by measuring several environmental variables. M. vimineum was sown within the microsites categorized. Differences in growth of M. vimineum across different microsites were quantified. As percent canopy cover increased, M. vimineum percent cover, mean length, and mean number of nodes decreased. Also, as litter depth increased, M. vimineum percent cover and stem length decreased. In undisturbed microsites in which M. vimineum was not sown, the exotic grass was not a dominant species, whereas in all other microsites created by logging machine operation M. vimineum was a dominant species whether those areas were sown or colonized by wild populations. These results suggest that unique microsites created by logging may facilitate M. vimineum invasion of central hardwood forests. The apparent connection between soil and canopy disturbance and invasion by M. vimineum provides further impetus for careful planning and use of haul roads and skid trails.

A 20-year Landsat water clarity census of Minnesota's 10,000 lakes

A 20-year comprehensive water clarity database assembled from Landsat imagery, primarily Thematic Mapper and Enhanced Thematic Mapper Plus, for Minnesota lakes larger than 8 ha in surface area contains data on more than 10,500 lakes at five-year intervals over the period 1985–2005. The reliability of the data was evaluated by examining the precision of repeated measurements on individual lakes within short time periods using data from adjacent overlapping Landsat paths and by comparing water clarity computed from Landsat data to field-collected Secchi depth data. The agreement between satellite data and field measurements of Secchi depth within Landsat paths was strong (average R 2 of 0.83 and range 0.71–0.96). Relationships between late-summer Landsat and field-measured Secchi depth for the combined statewide data similarly were strong ( r 2 of 0.77–0.80 for individual time periods and r 2 = 0.78 for the entire database). Lake clarity has strong geographic patterns in Minnesota; lakes in the south and southwest have low clarity, and lakes in the north and northeast tend to have the highest clarity. This pattern is evident at both the individual lake and the ecoregion level. Mean water clarity in the Northern Lakes and Forest and North Central Hardwood Forest ecoregions in central and northern Minnesota remained stable from 1985 to 2005 while decreasing water clarity trends were detected in the Western Corn Belt Plains and Northern Glaciated Plains ecoregions in southern Minnesota, where agriculture is the predominant land use. Mean water clarity at the statewide level also remained stable with an average around 2.25 m from 1985 to 2005. This assessment demonstrates that satellite imagery can provide an accurate method for obtaining comprehensive spatial and temporal coverage of key water quality characteristics that can be used to detect trends at different geographic scales.

Response of two oak species to extensive defoliation: Tree growth and vigor, phytochemistry, and herbivore suitability

This study was developed to experimentally determine whether the differential mortality of white oak versus black oak observed following defoliation events in the oak-dominated forests of the central hardwoods region of the eastern USA may be due to differences in carbon allocation between the two species. Black oak and white oak growing in a common garden were artificially defoliated (90%) using scissors in two consecutive years. Concurrent with the second defoliation event, herbivore performance and phytochemical characteristics were measured, followed immediately by measures of tree growth. In the dormant season following the second defoliation event, roots were sampled to assess tree vigor. Species-specific differences in foliar chemistry and herbivory were evident, regardless of defoliation. Defoliation-induced changes in above-ground biomass were evident in white oak, but not black oak. Defoliation-induced changes in foliar chemistry were more evident in black oak; these were reflected in greater differences in herbivore suitability. Herbivore consumption was correlated with depressed foliar C:N ratios and elevated foliar nitrogen. White oak root starch concentrations were markedly lower in defoliated trees, suggesting that white oak vigor is especially sensitive to resource limitations in the form of photosynthate loss. The implications of these results with respect to defoliation events and white oak mortality, as well as potential phylogenetic differences in response to severe defoliation between the red and white oak groups, are discussed.

Nine-Year Response of Hardwood Understory to Organic Matter Removal and Soil Compaction

Abstract The effects of three levels of organic matter removal (OMR) and three levels of soil compaction (SC) on the development of understory vegetation in a central hardwood forest were evaluated 9 years after treatments were applied as part of a national program of long-term soil productivityresearch. The three levels of biomass removal (OMR) were removal of merchantable boles only (OM0), removal of the whole tree (OM1), and removal of the whole tree plus forest floor (OM2). The three levels of soil compaction (SC) were none (C0), medium (C2), and severe (C2). Weeds were controlledin all plots for the first 2 years. Understory vegetation within 81 7.9-m2 subplots was inventoried by species and quantified into plant groups of woody (trees, shrubs, and woody vines) and herbaceous (annuals, perennials, and grasses) at year 5 (after 3 years of no weed control)and year 9 (after 7 years of no weed control). Vegetation was analyzed for nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg). OMR did not significantly affect the overall number of plants over the 5-year measurement period, but there were differences for both woodyvines and grasses, which were highest in the OM0 treatment in 1999, but by 2003, they were not different. There were no differences in plant numbers among plant groups for SC in the 1999 measurement period between treatments for any plant group, but there were significantly fewer trees andwoody vines in the C2 treatments than in the C0 or C1 treatments in 2003; the opposite was true for herbaceous annuals, which were highest in C1 and C2 treatments. Over the 5-year measurement period, only the height of woody vines was significantly affected by OMR, but SC significantly affectedthe height of all plant groups over the 5-year measurement period. Annually, however, trees were tallest in the OM0 and C0 treatment than in OM2 and C2 treatments. The annual height of other plants, excluding trees, was affected only 1 year of 5 by OMR. Fewer trees and shorter trees in thesevere compaction treatment suggest that, in the short term, soil productivity has been affected on the site.

Report on the Largest Known Occurrence of Morphological Anomalies in Ground Beetles (Coleoptera: Carabidae)

We report on one of the largest known occurrence of minor morphological anomalies in adult ground beetles (Coleoptera: Carabidae) in North America. Carabid beetles were caught in pitfall traps in 2006 in ash (Fraxinus spp.)-dominated stands in southeastern Michigan. About 10% and 32% of the trapped individuals and species, respectively, showed morphological anomalies that ranged widely from the presence of tumors, cysts, fossae, misplaced setae, and missing and fused elytral striae to incomplete pronotum. The genus Pterostichus Bonelli had the greatest numbers of anomalies that were present primarily on the elytra, although the head, pronotum, and abdominal sternites were also affected. Within species, Pterostichus melanarius (Illiger), the introduced European carabid beetle, had the greatest numbers of morphological anomalies. Slightly more females than males with anomalies were caught in these forest stands. The occurrence of such high numbers of morphological anomalies in adult beetles across the central hardwood forests is perplexing, and we suggest future studies focus on elucidating its causes within this forested landscape.

Thinning, fire, and oak regeneration across a heterogeneous landscape in the eastern U.S.: 7-year results

We document an increase in oak and hickory advance regeneration, depending on landscape position, in the sixth year following mechanical thinning and repeated prescribed fires in southern Ohio, USA. Oak-dominated communities provide a multitude of human and natural resource values throughout the eastern United States, but their long-term sustainability is threatened throughout the region by poor regeneration. This study was established to assess regeneration following midstory thinning (late 2000) and prescribed fire application (2001 and 2005) at two sites in southern Ohio. Each of the four 20+ ha treatment units (two thin and burn, two untreated controls) were modeled for long-term moisture regime using the integrated moisture index (IMI), and a 50 m grid of sampling points was established throughout the units. Vegetation and canopy openness were sampled at each gridpoint before and after treatments, in 2000, 2001, 2004, and 2006. The thin and burn treatment generally resulted in more advance regeneration (>50 cm height) of oak and hickory. The second fires in 2005 created additional landscape heterogeneity by causing variable tree mortality, and thus canopy openness, across the IMI gradient. The drier landscape positions generally had more intense fires, more canopy openness, and more oak and hickory advance regeneration; several other tree species also exhibited marked landscape variation in regeneration after treatments. Though advance regeneration of several competing species became abundant after the initial treatments, the second fires reduced the high densities of the two major competitors, Acer rubrum and Liriodendron tulipifera. Two simple models were developed: (1) a model of oak “competitiveness” based on the plot data related to advance regeneration of oaks and competitors and (2) a model estimating the probability of a plot becoming ‘competitive for oak’ based on canopy openness, IMI class, and number of oak and hickory seedlings present. For dry or intermediate sites with at least 5000 oak and hickory seedlings/ha, opening the canopy to 8.5–19% followed by at least two fires should promote oak and hickory to be ‘competitive’ over about 50% of the area. However, no appreciable oak and hickory regeneration developed on mesic sites. Overall, these results suggest promise for partial harvesting and repeated fires as a management strategy to reverse the accelerating loss of oak dominance in the central hardwoods region.

Growth, gas exchange, and root respiration of Quercus rubra seedlings exposed to low root zone temperatures in solution culture

Spring planting is standard operational practice in the Central Hardwood Region, though little is known about potential impacts of low root temperature (RT) common during spring on establishment success of temperate deciduous forest tree species. The effects of low RT on growth, gas exchange, and root respiration following winter dormancy were studied in 1-year-old northern red oak ( Quercus rubra L.) container seedlings grown in solution culture at uniform air temperatures, but exposed to three different root zone temperatures (10, 15, and 25 °C). After 14 days of treatment, net photosynthesis ( A), stomatal conductance ( g s), and transpiration ( E) were significantly affected by RT; however, these treatment effects did not persist for the remaining measurement period (days 21 and 28) despite growth reductions. After 28 days, new shoot length, leaf area, and number of new roots were reduced with decreasing RT. Shoot dry mass was higher in seedlings exposed to 25 °C compared with those in 10 °C, while an opposite trend occurred for root-to-shoot ratio. Leaf water potential ( ψ w) at day 28 and days to budbreak were not significantly altered by RT treatments. Root O 2 uptake in seedlings exposed to 10 °C was 65% lower than for those seedlings at 25 °C. Low RT has a physiological role in the control of root growth and root respiration, which could potentially affect establishment success of northern red oak seedlings planted in spring when soil temperatures are still low.

Influence of litter removal and mineral soil disturbance on the spread of an invasive grass in a Central Hardwood forest

Soil and litter disturbances within Central Hardwood forests may facilitate exotic plant species invasion of interior forest areas. Microstegium vimineum is an annual exotic grass that has become common throughout the Southeastern United States. Three replicates of three different mineral soil and litter disturbance treatments, plus a control with no disturbance, were established on the leading edge of M. vimineum patches prior to seed fall. All patches were located in areas with similar forest canopy structure and slope in three Central Hardwood forest stands prior to seed fall. At the beginning of the following growing season, each individual M. vimineum seedling was mapped within the treatment plots. The mean number of M. vimineum individuals that established within each treatment did not differ significantly from the control. The distance at which 90% of the individuals had spread, and the overall mean distance spread were significantly farther for the litter removal treatment than the control. The farthest individual seedling from the boundary of existing patches in both the litter removal and the mineral soil disturbance and litter removal treatments were significantly farther than the control. The individuals that spread the farthest are of most concern due to the large number of viable seed that a single M. vimineum plant can produce. These results suggest that disturbance of the litter layer may increase the spread rate of M. vimineum and facilitate its invasion of new habitats, and that leaving litter layers intact may slow the spread of M. vimineum.

Modeling the long-term effects of fire suppression on central hardwood forests in Missouri Ozarks, using LANDIS

Fire suppression has been found to dramatically change fire regimes, lead to accumulation of fuels, and alter forest composition and species abundance in the Central Hardwood Forests in the Missouri Ozarks, United States. After a half century of fire suppression, fire hazards have increased to a high level and high intensity fires are more likely to occur. We used LANDIS, a spatially explicit landscape dynamics model, to simulate the long-term effects of fire suppression on forests in Missouri Ozarks. Specifically, we examined to what extent fire suppression would affect fuel loads and fire hazards, and how fire suppression would affect forest tree species abundance. Using a spatial modeling approach, we conducted 200-year simulations of two management scenarios: (1) a fire suppression scenario circa 1990s and (2) a historic fire regime scenario prior to fire suppression, with a mean fire-return interval of 14 years. Under the fire suppression scenario, the simulation showed that both fine and coarse fuels were at a medium-high level after a few more decades of fire suppression. Fire hazard also rapidly increased to a medium-high level within a few decades. After one century of fire suppression, simulated fire intensity increased to a dangerous level, with more than 3/4 of the fires at a medium-high intensity level. Fire suppression also led to distinct changes in species abundance; the pine and oak–pine forests which used to dominate the study area prior to fire suppression were replaced by mixed-oak forests. This study suggests that it may be desirable to re-introduce frequent fire. By greatly increasing the use of fire over current management levels, our simulation suggests less accumulation of dangerous fuels, reduced fire hazard, and decreased occurrence of high intensity fires. Results imply that frequent fire would greatly increase the abundance of fire-resistant species (e.g., shortleaf pine) and decrease the abundance of more fire-sensitive species such as red oaks. Such a compositional shift should also decrease the recent phenomenon of widespread oak decline events.

Phenology model from surface meteorology does not capture satellite‐based greenup estimations

AbstractSeasonal temperature change in temperate forests is known to trigger the start of spring growth, and both interannual and spatial variations in spring onset have been tied to climatic variability. Satellite dates are increasingly being used in phenology studies, but to date that has been little effort to link remotely sensed phenology to surface climate records. In this research, we use a two‐parameter spring warming phenology model to explore the relationship between climate and satellite‐based phenology. We employ daily air temperature records between 2000 and 2005 for 171 National Oceanographic and Atmospheric Administration weather stations located throughout New England to construct spring warming models predicting the onset of spring, as defined by the date of half‐maximum greenness (D50) in deciduous forests as detected from Moderate Resolution Imaging Spectrometer. The best spring warming model starts accumulating temperatures after March 20th and when average daily temperatures exceed 5°C. The accumulated heat sums [heating degree day (HDD)] required to reach D50 range from 150 to 300 degree days over New England, with the highest requirements to the south and in coastal regions. We test the ability of the spring warming model to predict phenology against a null photoperiod model (average date of onset). The spring warming model offers little improvement on the null model when predicting D50. Differences between the efficacies of the two models are expressed as the ‘climate sensitivity ratio’ (CSR), which displays coherent spatial patterns. Our results suggest that northern (beech‐maple‐birch) and central (oak‐hickory) hardwood forests respond to climate differently, particularly with disparate requirements for the minimum temperature necessary to begin spring growth (3 and 6°C, respectively). We conclude that spatial location and species composition are critical factors for predicting the phenological response to climate change: satellite observations cannot be linked directly to temperature variability if species or community compositions are unknown.

Prescribed burning and understory composition in a temperate deciduous forest, Ohio, USA

Since the advent of widespread suppression in the mid-20th century, fire has been relatively rare in deciduous forests of the eastern United States. However, widespread prescribed burning has recently been proposed as a management tool to favor oak ( Quercus spp.) regeneration. To examine the potential effects of fire introduction on the understory community, we experimentally burned small plots and simulated aspects of fire at a forested site in southeastern Ohio. Treatments included two burn intensities, litter removal, increased soil pH, and a control. Treatments were arranged in a randomized block design in two landscape positions (dry upland and moist lowland) and two canopy conditions (gap, no gap). Post-fire vegetation was identified to species, and stems were counted 1, 3, and 14 months after burning. Community composition was more strongly affected by fire in upland plots than in lowlands, but was not affected by canopy openness. Both cool and hot burns reduced post-fire seedling emergence of Acer rubrum, a common overstory tree. Hot burns facilitated germination of Vitis spp., Rhus glabra, and Phytolacca americana, species common in disturbed habitats, and increased graminoid abundance. Cool burns and litter removal facilitated germination of Erechtites hieracifolia and Liriodendron tulipifera suggesting that litter removal is the mechanism by which fire favors colonization. These results suggest that fire applied frequently in the Central Hardwoods Region would cause compositional shifts to graminoids and disturbance-adapted forbs by increasing germination from the seed bank. Fire did not favor species with dormant underground buds, as studies in other ecosystems would suggest. Vegetational responses were noticeably weaker in the second year after burning, indicating that a single fire has only a short-term effect.

The effects of prescribed burning and canopy openness on establishment of two non-native plant species in a deciduous forest, southeast Ohio, USA

Fire has often been shown to promote invasion by non-native plant species, but few studies have examined the process in temperate-zone deciduous forests. To examine the potential of prescribed fire to facilitate invasions in the Central Hardwoods ecosystem, we experimentally burned small plots and simulated aspects of fire at a forested site in southeastern Ohio, USA. Treatments included high and low burn intensity, lime addition, and litter removal to test hypotheses of population limitation by fire intensity, fire-caused nutrient release, and removal of leaf litter, respectively. Treatments were arranged in a randomized block design in two landscape positions (dry upland, moist lowland) and two canopy conditions (gap, no gap). The experimental sites were not significantly different from randomly chosen forest sites in any of 12 environmental variables. Seeds of two problematic non-native species ( Microstegium vimineum and Rosa multiflora) were sown into plots following treatment to test the possibility of seed limitation. We recorded germination and height growth at three dates 1, 4, and 14 months following burning. Germination was promoted by litter removal and high- and low-intensity fire treatments in M. vimineum, and by high-intensity fire in R. multiflora. Seedling growth of both species was greatest following high-intensity fire under canopy gaps. Germination in the second year showed treatment effects similar to the first year indicating persistence of fire effects. Both species showed stronger recruitment in valleys and in canopy gaps, reflecting an interaction of fire and landscape position. We infer that prescribed burning and canopy-opening management practices have the potential to facilitate invasion of the study area by creating conditions promoting establishment and growth of at least two non-native species. The absence of these species in previous studies appears to be due to a lack of propagules rather than the unsuitability of forest sites for germination or growth.

Forest Succession in an Oak-Hickory Dominated Stand During a 40-Year Period at the Ross Biological Reserve, Indiana

Abstract Deciduous forests in the eastern United States have been dynamic over both geological and historical time scales, particularly since humans have modified the landscape. Historically, the central hardwood forest has been subject to considerable human disturbance, especially fire, and these anthropogenic disturbances have contributed to the dominance of shade-intolerant oak (Quercus) and hickory (Carya) species within the central hardwood region. Current research indicates that many of these forests are changing to dominance by shade-tolerant species, mainly sugar maple (Acer saccharum Marsh.). This change has been attributed to a lack of disturbance. The objective of this study was to document long-term changes in structure and composition of a mature oak-hickory stand at the Ross Biological Reserve in Indiana. There has been little disturbance at the Ross Biological Reserve in the past 55 years, and a similar trend of increased shade-tolerant species was expected. Results of decadal tree censuses...

Unusual Native Trees

Abstract In the central hardwoods region of the US, several small trees have potential for landscaping as either understory plants or in full sun where their fall color, wide adaptability, and apparent resistance to pests make them attractive. I outline 6 species of deciduous trees, representing the genus Sassafras, Oxydendron, Nyssa, Cladrastis, Cephalanthus, and Viburnum, that I find particularly interesting and deserving of more widespread use.

Tree Cavity Resources for Dependent Cavity-Using Wildlife in West Virginia Forests

Abstract We assessed and compared tree cavity resources for dependent wildlife among various forest cover types of West Virginia. The study was conducted in the Greenbrier and Potomac Ranger Districts of the Monongahela National Forest (MNF). From the fall of 1999 through the spring of 2001, 25 50-m radius study plots were established in each of a Society of American Foresters (SAF) central hardwood, northern hardwood, and subalpine forest cover type. Cavity tree abundance significantly differed among the three forest cover types (P < 0.0001), with the highest cavity tree abundance in the central hardwood type (x¯ = 16.4; SE = 5.3), followed by the northern hardwood type (x¯ = 12.7; SE = 6.8), and lastly the subalpine type (x¯ = 7.2; SE = 3.6). Relative cavity likelihood was highest for black locust (Robinia pseudoacacia), followed by American beech (Fagus grandifolia), sugar maple (Acer saccharum), and chestnut oak (Quercus prinus). American beech cavity numbers currently may be influenced by increased mortality from recent outbreaks of beech bark disease, initiated by the beech scale insect (Cryptococcus fagisuga). Management of red spruce (Picea rubens) forests should consider numbers of nearby large hardwoods to provide cavity resources for dependent wildlife.