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Although the Cooperative Wildlife Research Unit Program is nationwide in scope and has been in existence since 1935, it is probable that many readers of the Journal of Forestry are unaquainted with the program's objectives and accomplishments. This paper was written at the suggestion of a S.A.F. member to provide such information.
Bottomland hardwoods are floodplain forests along rivers and streams throughout the southeastern United States. The interrelations among hydrology, soils, geomorphic landforms, and tree species composition are the foundation of forest management in bottomland hardwoods, and historically their correspondence has allowed for somewhat predictable forest responses based upon the hydrogeomorphic setting. However, extensive hydrologic and geomorphic modifications in floodplains have disrupted these interrelations and, on many sites, have created novel disturbance regimes resulting in unpredictable forest responses. Reduced or altered timing of surface flooding and groundwater declines are common in the region and have favored increases in stem densities, particularly of species less tolerant of flooding and more tolerant of shade. In these highly modified systems, more process-level understanding of floodplain hydrology, soil moisture dynamics, interspecific tree competition, and regeneration is needed to develop more effective management prescriptions and for forestry to be represented in integrated water-resource management decisions.
Geospatial patterns of forest fragmentation over the three traditional giant forested areas of China (Northeastern, southwestern and Southern China) were analyzed comparatively and reported based on a 250-m resolution land cover dataset. Specifically, the spatial patterns of forest fragmentation were characterized by combining geospatial metrics and forest fragmentation models. The driving forces resulting in the differences of the forest spatial patterns were also investigated. Results suggested that forests in southwest China had the highest severity of forest fragmentation, followed by south region and northeast region. The driving forces of forest fragmentation in China were primarily the giant population and improper exploitation of forests. In conclusion, the generated information in the study provided valuable insights and implications as to the fragmentation patterns and the conservation of biodiversity or genes, and the use of the chosen geospatial metrics and forest fragmentation models was quite useful for depicting forest fragmentation patterns. ?? 2008 Northeast Forestry University.
Quantification of biomass is fundamental to a wide range of research and natural resource management goals. An accurate estimation of plant biomass is essential to predict potential fire behavior, calculate carbon sequestration for global climate change research, assess critical wildlife habitat, and so forth. Reliable allometric equations from simple field measurements are necessary for efficient evaluation of plant biomass. However, allometric equations are not available for many common woody plant taxa in the Sierra Nevada. In this report, we present more than 200 regression equations for the Sierra Nevada western slope that relate crown diameter, plant height, crown volume, stem diameter, and both crown diameter and height to the dry weight of foliage, branches, and entire aboveground biomass. Destructive sampling methods resulted in regression equations that accurately predict biomass from one or two simple, nondestructive field measurements. The tables presented here will allow researchers and natural resource managers to easily choose the best equations to fit their biomass assessment needs.
A K--8 school in a suburb of St. Paul has formed a partnership with natural resource professionals to create a school forest for environmental education in the field. The university and agency professionals worked with students to teach them the skills necessary to map and inventory their school grounds. Students then used the inventory data to develop a school forest plan. Over the past four years students have been implementing their plans for both field and classroom work and cross-curricular activities. With the program entering its fifth year, we can advise others looking for similar opportunities.
A study of fuels in Sierra Nevada conifer forests showed that fuel bed depth and fuel bed weight significantly varied by tree species and developmental stage of the overstory. Specific values for depth and weight of woody, litter, and duff fuels are reported. There was a significant positive relationship between fuel bed depth and weight. Estimates of woody fuel weight using the planar intercept method were significantly related to sampled values. These relationships can be used to estimate fuel weights in the field.
In eastern North America, white-tailed deer ( Odocoileus virginianus ) can have profound influences on forest biodiversity and forest successional processes. Moderate to high deer populations in the central Appalachians have resulted in lower forest biodiversity. Legacy effects in some areas persist even following deer population reductions or declines. This has prompted managers to consider deer population management goals in light of policies designed to support conservation of biodiversity and forest regeneration while continuing to support ample recreational hunting opportunities. However, despite known relationships between herbivory intensity and biodiversity impact, little information exists on the predictability of herbivory intensity across the varied and spatially diverse habitat conditions of the central Appalachians. We examined the predictability of browsing rates across central Appalachian landscapes at four environmental scales: vegetative community characteristics, physical environment, habitat configuration, and local human and deer population demographics. In an information - theoretic approach, we found that a model fitting the number of stems browsed relative to local vegetation characteristics received most (62%) of the overall support of all tested models assessing herbivory impact. Our data suggest that deer herbivory responded most predictably to differences in vegetation quantity and type. No other spatial factors or demographic factors consistently affected browsing intensity. Because herbivory, vegetation communities, and productivity vary spatially, we suggest that effective broad-scale herbivory impact assessment should include spatially-balanced vegetation monitoring that accounts for regional differences in deer forage preference. Effective monitoring is necessary to avoid biodiversity impacts and deleterious changes in vegetation community composition that are difficult to reverse and/or may not be detected using traditional deer-density based management goals.
Given high likelihood of regional extirpation of several once-common bat species in eastern North America from White-nose Syndrome, it is critical that impacts of forest management activities such as prescribed fire are known to minimize potentially additive negative effects on bat populations. Historic wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning, implementing and assessing burning programs going forward. To examine effects of historic fire on bats, we sampled bat activity at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park (SNP), Virginia, USA, 2015. We found limited evidence positive fire effects over time on hoary bats (Lasiurus cinereus) and big brown bats (Eptesicus fuscus) occupancy. Overall, we found few or mostly equivocal relationships of bat occupancy relative to burn condition or time since fire at SNP across species using a false-positive occupancy approach. Our results suggest that fire does not strongly affect bat site occupancy at short or long-term time scales in the central Appalachians.
Overstory basal area, ericaceous shrub cover ( Kalmia latifolia L. and Rhododendron maximum L.), and fuels (i.e., woody fuel loads and depths and O Horizon thickness) were assessed within Great Smoky Mountains National Park, USA, in 2003 − 2004. Due to recent wildfire activity within the southern Appalachian Mountain region (including Great Smoky Mountains National Park), the potential spread and expansion of ericaceous shrubs, and the impacts of the hemlock woolly adelgid ( Adelges tsugae Annand) on eastern hemlock ( Tsuga canadensis (L.) Carrière), these same ecosystem components were again assessed in 2019. Elevation and moisture regime (xeric, intermediate, and mesic) were included in this assessment as potential influential factors. An evaluation of repeated measurements from 40 plots suggested that O Horizon thickness did not change significantly over the 16-year period, but increased as elevation increased, and moisture regime (xeric O Horizon thickness > mesic O Horizon thickness) was a significant, related factor. The sum of 1-, 10-, and 100-h fuel loads (fuels less < 7.6 cm diameter) increased, whereas woody fuel depth decreased over the 16-year period. No significant changes in 1000-h fuel loads (> 7.6 cm diameter), total woody fuel loads, ericaceous shrub cover, total basal area, or live T. canadensis basal area were observed. Live T. canadensis basal area decreased with increasing elevation. Dead, standing T. canadensis basal area increased from 2003–2019, and that increase was most pronounced as elevation increased on xeric and intermediate sites. Overall, we found that: 1. hypothesized increases in total woody fuel loads and ericaceous shrub cover were not present; and 2. elevation and moisture regime were most related to observed changes in vegetation and fuel condition.
Wildfires elicit a perceived need for emergency action to stabilize denuded landscapes. Aerial seeding of rapidly growing nonnative grasses is used routinely in an attempt to control postfire erosion, despite limited scientific basis for its effectiveness and with little consideration for its unintended ecological impacts. As fire size and magnitude have increased in recent decades, so has the prevalence and cost of postfire seeding and the potential footprint of its unintended impacts. We see a growing consensus in the research community on two important points: this management practice often is not cost-effective and it appears to create more problems than it solves.
No abstract available.
Summary: The history of field investigations of the effects of DDT on wildlife is reviewed briefly, from the initial studies in 1945 through the more recent studies of the effects of the large-scale programs for spruce-budworm control and gypsy-moth eradication. DDT dosages and procedures that are recommended for protection of wildlife are reviewed. Effects of aldrin, heptachlor, and toxaphene are discussed in connection with the grasshopper and Mormon cricket control programs. Delayed and indirect effects of chemical treatments are emphasized as an important current problem. Cited in this connection are fish losses in the Yellowstone and Miramichi rivers and losses of wildlife from eating earthworms a year after treatment of the area with DDT. Currently recommended procedures to safeguard wildlife in pesticidal programs are listed.
Wetland is part of a continuum of land types between deep water and dryland. Only one wetland classification was available for the United States prior to preparation of the new system described here, but numerous regional and special-purpose classifications are in use. The new classification is hierarchical, progressing from five systems (marine, estuarine, lacustrine, riverine, and palustrine) at the most general level to dominance types based on plant or animal communities at the most specific level. The system is currently in use for prototype maps of wetlands of the United States. It is hoped that it may be incorporated into a classification of all land.
In Yosemite National Park, 92 percent of the parties using back country areas had permits. Parties without permits were smaller in size and stayed for shorter periods of time. For all parties with permits, 62 percent made changes to their trips. Parties changing their trips in both time and space accounted for 27 percent of the total, while 14 percent made temporal changes only, and 21 percent made spatial changes only. Use estimates can be adjusted by multiplying by 1 + C + Δ where C is the noncompliance factor and Δ is the change factor for compliers. While the combined effect of these factors on total visitor nights for the Yosemite backcountry was an overestimation of 12.5 percent, areas near trailheads received heavier use and outlying areas received lighter use than permits indicated.
The National Fire Danger Rating System and the Fire Behavior Prediction System were tested on prescribed fires burning underneath canopies in six fuel types in Yosemite National Park, California. The mean error for rate of spread was +0.03 foot per minute for the NFDRS and -0.15 foot for the FBPS. For flame length the mean error was -0.38 foot for both systems. Regressions provided factors for correcting predicted values. Burning prescriptions based on the models have been adjusted for the variation in their predictive capability.