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Characteristics of nest trees used by 4 species of cavity-nesting birds were investigated in a northern hardwood forest in Vermont. A total of 110 nests was found for the yellow-bellied sapsucker (Syphrapicus varius), hairy woodpecker (Picoides villosus), downy woodpecker (P. pubescens), and black-capped chickadee (Parus atricapillus). The 110 nest trees were compared to 440 selected non-nest trees to identify tree characteristics associated with the presence of active cavity nests. Criteria to identify potential cavity-nest trees were developed. Woodpecker and sapsucker nests were associated with live, deciduous trees with fruiting bodies of heartwood decay fungi, branch stubs, broken tops, or previously excavated cavities. Chickadees used well decayed, deciduous snags with broken tops. J. WILDL. MANAGE. 51(1):217-223 Primary cavity-nesting birds excavate their own nest holes and are dependent upon trees suitable for excavation; hence populations may be limited by potential nest sites. Previous studies have confirmed that primary cavity-nesting birds have specific requirements for nest sites (Kilham 1971, Conner et al. 1976) and that territory selection and reproductive success depend on the presence of suitable nest sites (von Haartman 1957, Kilham 1966). Shortages of potential cavity-nest sites may exist in young forests (Flack 1976) and in all ages of intensively managed forests (McClelland 1977, Carey 1983). Suitable nest sites for primary cavity-nesting birds are generally considered to be old, dead or dying, partially decayed trees. Timber management practices uch as clearcutting, timber stand improvement, short harvest rotations, and removing snags to reduce fire and safety hazards may result in elimination of cavity-nest sites from the forest. It should be expected that unmanaged timber stands will have higher densities of cavity trees and snags than managed stands (Cline et al. 1980). Furthermore, as the use of wood for energy production continues to increase, trees formerly regarded as unmerchantable will be harvested extensively. Our study was designed to provide information needed to manage for trees suitable for 'Present address: Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology, University of Wyoming, Box 3166, University Station, Laramie, WY 82071. This content downloaded from 157.55.39.177 on Fri, 18 Nov 2016 04:13:55 UTC All use subject to http://about.jstor.org/terms 218 CAVITY-NEST TREES * Runde and Capen J. Wildl. Manage. 51(1):1987 nesting use by primary cavity-nesting birds in a northern hardwood forest. The objective was to identify characteristics of nest trees used by 4 species of primary cavity-nesting birds. This study was funded by the Windham Found., Grafton, Vt. and Coop. For. Res. Funds administered through the School Nat. Resour., Univ. Vermont. We thank W. P. Roberts, S. G. Parren, F. R. Thompson, and M. R. Scott for assistance in the field. J. D. Gill and M. G. Raphael provided helpful suggestions on the manuscript. STUDY AREA AND METHODS This study took place on the University of Vermont's Grafton Forest Resource Project Area, a 1,225-ha site in the eastern foothill region of the Green Mountains of southeastern Vermont. Elevations range from 260 to 550 m. Acidic, glacial till soils predominate. Most of the study area is an all-aged mix of northern hardwoods and conifers. Hardwood cover types occur on 56% of the area, softwood types on 26%, and mixed types on 8%. Miscellaneous or agricultural types make up 10% of the area. Early forest seral stages are composed primarily of white pine (Pinus strobus), paper birch (Betula papyrifera), red maple (Acer rubrum), and quaking aspen (Populus tremuloides). Older stages are primarily American beech (Fagus grandifolia), yellow birch (B. alleghaniensis), and sugar maple (A. saccharum), with lesser amounts of Canada hemlock (Tsuga canadensis), northern red oak (Quercus rubra), white ash (Fraxinus americana), and American hophornbeam (Ostrya virginiana). Red spruce (Picea rubens), balsam fir (Abies balsamea), paper birch, and northern red oak occur on shallow soils at higher elevations. We examined active nest sites of 4 species of primary cavity-nesting birds: yellow-bellied sapsuckers, hairy woodpeckers, downy woodpeckers, and black-capped chickadees. These common birds reflect a range of excavation ability in cavity nesters of the Northeast. Hairy woodpeckers are the strongest excavators, followed by yellow-bellied sapsuckers, downy woodpeckers, and black-capped chickadees. Nest searching began 1 May and ended 15 July in 1979 and 1980. Early in the breeding season, nests were found by observing birds exhibiting territorial, nest building, or courtship behaviors. Several territories of the yellow-bellied sapsucker were located by imitating their territorial tapping. Later in the season, nests were found by listening for nestlings calling from within a nest or by observing adults carying food into a cavity. We identified "cavity trees" as those with excavated or natural cavities and classified "potential cavity trees" as those exhibiting characteristics that indicated potential for excavation. In this paper only standing dead trees >5 m tall are referred to as "snags"; dead trees 5-cm penetration by a knife blade. We noted whethr the top of each tree was broken or intact, and whether the tree was living. Adjacent nonnest trees were measured as nest trees, except no increment cores were taken, and dnh was measured at the height of the adjacent nest hole. We characterized nest trees and compared them to non-nest trees by testing with the Chisquare statistic whether the proportion of nest trees with a given characteristic was equal to the proportion of non-nest trees with the same characteristic. Differences in sizes of nest and non-nest trees were identified using Student's This content downloaded from 157.55.39.177 on Fri, 18 Nov 2016 04:13:55 UTC All use subject to http://about.jstor.org/terms J. Wildl. Manage. 51(1):1987 CAVITY-NEST TREES * Runde and Capen 219 t-test. To provide a more rigorous 1-sided t-test for differences between upper stem diameters and total height of nest and non-nest trees, we excluded non-nest trees known to be out of the size range of active nest trees. For woodpecker species, non-nest trees were included only if dbh was >20 cm (min. dbh of woodpecker nest trees in this study). For black-capped chickadees, nonnest trees were included if dbh was

The relationship between bald eagles (Haliaeetus leucocephalus) and their winter habitat was examined at 5 communal roosts in the Klamath Basin of southern Oregon and northern California. Bald eagle communal roosts were in forest stands with old (mean age of roost trees = 236 years), open-structured trees closest to the feeding areas. Mean characteristics of forest stands at the 5 roosts were: density, 53.1 trees/ha; dbh, 54.3 cm; height, 26.4 m; percent spikes and snags, 7.2. Roost trees were generally larger and more open in structure than surrounding stand characteristics (dbh, 69.6 cm; height, 28.2 m; percent spikes and snags used, 15.6). Douglas-fir (Pseudotsuga menziesii) occurred in only 1 roost and was used for roosting in a much greater proportion than it occurred. The remaining 4 roosts were nearly single species stands of ponderosa pine (Pinus ponderosa). Management guidelines are suggested to maintain suitable wintering roost habitat for bald eagles. J. WILDL. MANAGE. 47(4):1072-1079 Bald eagles are listed as "Endangered" in 43 states and "Threatened" in Michigan, Wisconsin, Minnesota, Oregon, and Washington (Lincer et al. 1979). In fall, bald eagles migrate from areas of harsh climates to areas with milder climates and available food. There were 12,199 wintering bald eagles counted in the 48 contiguous states in the 1980 National Wildlife Federation census. In the western United States, major concentrations occur from the southern Alaskan coast to northern California. The peak winter population of bald eagles in the Klamath Basin of southern Oregon and northern California was 500 during winter 1976-77 (G. D. Krauss, unpubl. rep., Klamath Natl. For., 1977), 1978-79, and 1979-80 (Keister 1981). This population represents 1 of the highest densities of wintering bald eagles in the 48 contiguous states. Few studies conducted on wintering bald eagles in North America have quantitatively described night communal roosts (Lish 1973, Griffin 1978, Hansen et al. 1980, Steenhof et al. 1980, Anthony et al. 1982). The purpose of this paper is to describe forest stand characteristics at 5 communal roosts in the Klamath Basin of southern Oregon and northern California. This study was conducted under the auspices of the Oregon Cooperative Wildlife Research Unit; Oregon State University, Oregon Department of Fish and Wildlife, U.S. Fish and Wildlife Service, and the Wildlife Management Institute cooperating. The U.S. Fish and Wildlife Service and The Nature Conservancy funded the study under contract 14-16009-79018. This is Oregon State University Agricultural Experiment Station Technical Paper 6190. We thank R. Fields, R. Opp, and D. Sassey for help with data collection. R. McClelland, S. Thompson, J. Crawford, F. Isaacs, D. Faukenberry, and K. Steenhof reviewed drafts of the

Deadwood is one of the four elements taken into account in this review of indicators and field methods and is often considered as a key indicator of forest biodiversity. We have analysed the main types of surveys and have realised how greatly the needs and constraints used to monitor deadwood can vary among them. For instance, classical National Forest Inventories usually tend to avoid time-consuming collecting methods. In the wide variety of existing definitions of deadwood, such inventories require simple and clear definitions, especially in terms of quantified thresholds. Thus, deadwood is properly described by characterising several components, such as snags, logs, stumps, branches and fine woody debris. Deadwood sampling methods alter depending on the different components and dimensions considered (standing dead trees, lying dead trees and branches, etc. assessed quantitatively). Attributes such as tree species and stage of decay are used mainly to qualify the deadwood components. The deadwood volume estimations are usually based on classical approaches already applied to living or felled trees: volume equations and/or formulas giving the volumes of common geometric solids. The purpose of this paper is to focus on different deadwood assessment techniques and to provide the information necessary to identify the most relevant methods for collecting deadwood data. The latter is used to build indicators that characterise the evolution of forest biodiversity at the scale of large forest territories.

International audience; This paper reviews the effects that windstorm-induced drastic changes (micro-climate, soil, vegetation, and ground structural heterogeneity) have on forest insect communities. In the current context of shady and CWD-deprived managed forests, windthrow gaps act as regional biodiversity hotspots by maintaining habitat continuity in a mosaic landscape, and by facilitating the breeding and population growth of clearing specialists and saproxylic species. Windthrow gaps are dead-wood islands where forest protection and habitat conservation goals may stand against each other. Besides the quantitative effect of dead wood on bark beetle outbreaks and saproxylic diversity, the latter is favoured by key dead-wood micro-habitats such as large logs, snags and sun-exposed coarse woody debris. The role of natural enemies and sanitation operations in regulating pest outbreaks is discussed. Heterogeneous openings provide many micro-habitats favouring flower-visiting insects, phytophages on saplings, on fallen tree crowns, and on diverse understory flora, as well as ground insects on specific micro-sites.

Management of coarse woody debris following fire requires consideration of its positive and negative values. The ecological benefits of coarse woody debris and fire hazard considerations are summarized. This paper presents recommendations for desired ranges of coarse woody debris. Example simulations illustrate changes in debris over time and with varying management.

Forest edges created by dispersed-patch clear-cutting have become a con- spicuous landscape feature in western North America, but the effects of edge on forest structure and function are still poorly understood. In this paper we describe responses of stocking density, growth, mortality, and regeneration for three conifer species from the clear-cut edge into the interior of old-growth forest patches adjacent to 10-15 yr old clearcuts in southern Washington and central Oregon. The significance of edge effects for each variable was tested through a single-factor (distance) analysis of variance (F test). Relationships between these variables and depth-of-edge influence (i.e., edge width) on old-growth forest were characterized by nonlinear regression models. Near the edge (forest-clearcut boundary line), the old-growth forest has (1) reduced stocking density, as measured by canopy cover, number of stems per hectare, and basal area; (2) increased growth rates of dominant Douglas-fir (Pseudotsuga menziesii) and western hemlock (Tsuga heterophylla), as calcu- lated by an index of relative growth rate; (3) elevated rates of tree mortality, as measured by standing dead and down trees (snags and logs); and (4) greater numbers of Douglas-fir and western hemlock seedlings (

Empirical studies of the effects of forestry on cavity-nesting birds largely neglect weak cavity excavators and instead focus on large, strong cavity excavators such as woodpeckers (Picidae). Weak cavity nesters tend to be smaller and may be less limited by the availability of large trees but more dependent on suitably softened wood. In this paper, we describe availability, use, and preference for nesting habitat of a small cavity-nesting bird, the red-breasted nuthatch (Sitta canadensis), in mature coniferous forest in southeastern British Columbia. We describe nesting habitat at 3 spatial scales: (1) the level of forest stands proposed for logging (cutblocks), which ranged from 8.1 to 18.4 ha in size; (2) the level of 0.04-ha patches of forest centered on nest trees (nest plots); and (3) the level of individual nest trees. In addition to considering basic structural habitat features, we analyzed the relation between nesting use and several factors related to forest health, including Armillaria root disease (Armillaria ostoyae), stemwood decay, mountain pine beetle (Dendroctonus ponderosae) infestation, and dwarf mistletoe (Arceuthobium spp.). Red-breasted nuthatches nested at higher densities on cutblocks with more dead trees (snags) and higher levels of root disease. Within nest plots, we also detected a preference for nesting in Armillaria-infected trees. Cavity nesting of nuthatches was influenced by both forest structure and the disease agents that contribute to it. We recommend that standing diseased and dead trees be retained in patches during logging operations. Retention of such trees in distinct patches more likely satisfies requirements for worker safety and for limiting the spread of diseases than does retention of single dead and diseased trees throughout cutblocks. Wildlife values not only should be incorporated into timber harvesting regulations but also should be considered when planning activities designed to improve forest health for timber production.

The ringtail (Bassariscus astutus) attains the northern limit of its range in southwestern Oregon (Hall 1981:964, map 500). In Oregont as in most regionsJ B. astutus is not abundant; estimates of density elsewhere usually are < 5 per km2 (Poglayen-Neuwall and Toweill 1988). It is classified as a "sensitive species-undetermined status't by the Oregon Department of Fish and Wildlife "based on infrequent sightings or reports" and is afforded protection "against taking in Oregon by state administrative rule" (Marshall 1992:RING 1). Other than information contained in general works on mammals (e.g./ Bailey 1936), we know of no published report concerning any aspect of the biology of B. astutus in Oregon. Knowledge of the species elsewhere is fragmentary, especially in comparison with that of most other North American carnivoresX In 1992, a project was initiated by one of us (TPF) to investigate several aspects of the ecology of B. nstutus in the Myrtle Creek drainage, a tributary of the South Umpqua River, northeast of Myrtle Creek, Douglas Co., Oregon (T 28 S, R 3-4 W). Habitats occupied by B. astutus were in Douglas-fir (Pseudotsuga menziesii) forest at elevations of 450-550 m. Most of the area was occupied by regenerating 5-30-yr-old clear-cuttings with older Douglas-fir forest and riparian hardwoods interspersed. Bassariscus astutus usually denned in 15-30-m Douglas-fir snags, but dens occasionally were located in brush piles, downed logs, and stumps. Fifty-six fecal droppings were collected at entrances to dens or at the base of trees containing dens occupied by five B. astutus to which beacon radio transmitters were attached. Dens and individuals were located and identified by radio signals at unique frequencies; nevertheless, all fecal droppings may not have been deposited by the radio-tagged individual occupying a specific den. Herein, we report on the diet of B. astutus in Oregon based on our examination and identification of food remains in those fecal droppings. Fecal droppings were placed in plastic bags, labeled, and frozen. Examination of the droppings followed procedures outlined by Korschgen (1980). Briefly, individual fecal droppings were softened by soaking in water then teased apart and the material distributed fairly evenly over 21 x 32-cm white-enameled trays. Materials that could not be identified in the trays or when picked out and examined under a 7-30 x binocular microscope were dried on paper towels and placed in labeled envelopes for subsequent comparison with museum specimens or identification by specialists of specific taxonomic groups. Results are reported by frequency of occurrence and percent frequency of occurrence by month (Table 1); samples were available for 9 of the 12 months. The diet of B. astutus in Oregon (Table 1) is similar to that reported for the species elsewhere in that it is omnivorous (Grinnell et al. 1937; Taylor 1954; Trapp 1978; Toweill and Teer 1977). Similar proportions of fecal samples contained materials of plant and animal origin (Table 1). Plant material occurred in 93% of the samplesr similar to the 90.6% reported by Toweill and Teer (1977) for the Edwards Plateau in Texas. Trappe (1978) reported 46% of samples from Utah contained fruits, 17% miscellaneous vegetable matter, and 4% graminoids, considerably less frequent than we found among Oregon samples (even if the Utah frequencies were additive). Direct comparison of our findings with those of Taylor (1954), Wood (1954), and Davis (1960) conducted in Texas was not possible because they did not present data by frequency of occurrence. In our study, leaves, scales, and bracts of several conifers; wood; moss; and lichens were consumed throughout the year, whereas berries and seeds were consumed only during summer (August-September; Table 1). Conifer leaves were incorporated into the feces, not merely stuck to themr indicating that the leaves actually were ingested, but on passing through the digestive tract of B. astutus, the leaves exhibited little change. Most other items in the feces were well masticated and/ except for hard items (bone, teeth, chitin, seeds, hair, and cellulose), heavily digested. Ninety-one percent of the samples also contained animal material. Mammal remains were tound in 66% of the samples, considerably more frequent than the 13.7% reported by Toweill and Teer (1977) in Texas, and slightly more than the 55% reported in Utah (Trapp, 1978). Murid rodents were the largest component of the mammalian food items (Table 1), likely reflecting the nocturnal foraging habits of B. astutus (Poglayen-Neuwall and Toweill 1988). Among mammals represented, the red tree vole (Phenacomys longicaudus) occurred most frequently. The house cat (Felis catus), represented

When trees are dying in large numbers in a forest stand, it is usually assumed they are dying from a disease. Therefore, the study of stand-level dieback has traditionally been the concern of the forest pathologist and pest entomologist. However, stand-level dieback is not always caused by biotic agents, and the term as defined in this paper refers to stands of dead or dying trees whose dieback cause is not obvious and that typically occur in several locations of a larger forest ecosystem. In such stands, adjacent trees as well as spatially separated trees die more or less simultaneously, and loss of foliage usually begins from the top downwards. Dieback trees may be identified either as standing snags or as still living but stag-headed trees. Such dieback stands are common in many indigenous Pacific forests (41), and they have received attention also in several North American (32) and European forests (9). The recent emphasis on the dieback of forests in industrial countries has enlarged the group of researchers to include soil scientists, foresters, and pollution specialists. In both the pathological and air pollution research of dieback, the structure of the forests with dieback, their spatial and temporal patterns, their habitat relationships, and their associated vegetation and successional re­ sponses have received less attention than the more immediate symptoms and assumed causes. However, to arrive at a more complete etiology, such vegetation structural aspects should be analyzed with equal effort. Without such effort, it is difficult to distinguish commonalities and discrepancies in stand-level dieback of different forest biomes. For example, Jimenez et al (21) described stand-level dieback in mangrove forests as "mass mortality" and suggested that mass diebacks always have an abiotic rather than biotic cause. Their distinction between mass mortality and normal mortality is helpful in understanding natural dieback, but when larger and smaller areas of

Solder joint integrity is recognized as a key issue in the reliability of electronic devices. In the past decades, SnAgCu eutectic based solders are replacing SnPb eutectic solders in the electronics industry. Although the Pb-free solder is usually regarded as having a higher melting temperature compared with traditional Pb-Sn eutectic solder, solder joints were generally operated at a high homologous temperature, and exhibit complex rate-dependent behaviors. An advanced constitutive model for SnPb and SnAg solder materials is developed in this paper. A unified creep-plasticity constitutive law is adopted to simulate the complex inelastic behaviors of SnPb and SnAg solders. Damage during fatigue loading is predicted using continuum mechanics based method. The hardening of solders is considered combining both isotropic and nonlinear kinematic hardening. The developed model was incorporated into a finite element code. The mechanical properties and damage accumulation of both SnPb and SnAg solders were analyzed. Fatigue life under fully reversed cycling is investigated by monitoring the changing of peak stresses, which will decrease continuously due to damage accumulation. The numerical results were compared with experiment data and shows that the developed model can predict the stress-strain relationship and damage accumulation process of solder materials with reasonable accuracy.

In live trees availability of dens with entrances -2.5 cm in diameter for secondary cavity users was summarized by forest type, cover type, stand age, land ownership, stand origin, and physiographic site in Florida and South Carolina. Den density was lowest in slash pine (Pinus elliottii) and longleaf pine (P. palustris) stands and highest in oak (Quercus spp.)-tupelo (Nyssa spp.)-baldcypress (Taxodium spp.) stands. Stands ?61 years old had 3-20X more dens than 0-30-year-old stands. Soft hardwoods and oaks; particularly blackgum tupelo (N. sylvatica var. aquatica), water tupelo (N. aquatica), red maple (Acer rubrum), and laurel oak (Q. laurifolia) were cavity prone. Dens were rare in southern yellow pines (Pinus spp.). In Florida den trees were consistently larger in diameter than live trees without cavities, and most dens (70-85%) in pine, pine-hardwood, hardwood, and tropical hardwood forests were 60-year rotations are recommended to maintain 100% of potential populations of secondary cavity users. J. WILDL. MANAGE. 50(4):584-591 Considerable attention has been given to management of forest stands in harmony with snag (dead tree) availability, but little information is available on simultaneous management of forest stands for den trees (live cavitybearing trees) and timber. Den trees supplement cavities in snags and may remain standing longer than snags (Carey 1983). Up to 84% of all cavities in some forest types occur in trees that are at least partially alive (Carey 1983). Use of dens by secondary cavity nesters is well documented. Dens in live trees should be included in estimates of cavity availability. Specific requirements for snags and den trees by secondary cavity users have been documented for scattered geographical areas (Sanderson et al. 1976, Van Balen et al. 1982, Harlow and Guynn 1983, Huntley 1983), but timber stand improvement (TSI) in any forest stand reduces cull tree abundance and may reduce den tree availability to secondary cavity nesters. Cavity characteristics and availability vary among forest types, stand ages, and stand histories (McComb 1979, Huntley 1983, Moriarty and McComb 1983). One complicating factor in any comparisons made among published results is an inconsistent definition of "cavity" or "den" in the literature. For example, a minimum den entrance diameter of 5 cm will result in an exponentially or curvilinearly higher estimate of dens/unit area than if a larger minimum entrance diameter were used. The objectives of our study were to: (1) summarize den densities for each of the predominant forest types, cover types (pine, pine-hardwood, hardwood, and tropical), age classes within cover types, land ownership groups within cover types, and stand origin classes within cover types in Florida and South Carolina; (2) identify cavity-prone tree species in Florida and South Carolina; and (3) quantify den entrance and height characteristics in Florida. We thank M. A. McPeek, C. E. Rowell, and the Univ. Kentucky Comput. Cent. staff who assisted with initial analyses and with logistical problems and P. L. Groetsch, W. R. Marion, T. E. O'Meara, L. A. Caine, E. D. Land, R. N. Conner, R. A. Lancia, and J. D. Gill for reviewing a draft of the manuscript. The information reported in our paper (85-8-174) was prepared in connection with Ky. Agric. Exp. Stn. Proj. 624 in cooperation with the U.S. For. Serv.; it is published with the approval of the Director.

Birds were counted during the breeding season from 1977 to 1981 in 4 snag and 4 snagless plots (80 X 250 m) in an east Texas clear-cut to assess effects of snag retention on the bird community. After 4 years, 44 of the original 75 snags remained. Species richness, bird abundance, bird species diversity, and equitability were all higher (P < 0.05) in plots with snags than in snagless plots. Cavity-nesting birds occurred on plots with snags but were virtually absent from snagless plots. Other species used snags for foraging and perching and were more abundant on plots with snags. Retention or creation of snags is recommended for bird management in clear-cuts. J. WILDL. MANAGE. 47(3):799-804 Increased demand for wood products (U.S. Dep. Agric. 1973) has brought more intensive management of forests. Lands are being fully stocked with fast-growing trees and harvest rotations are being shortened. Present management trends increase homogeneity of commercial forests. Decaying wood in forest stands has no commercial value and is being eliminated. High-yield timber management replaces stands of snags (dead or dying trees) and old growth with young vigorous stands. Forest birds evolved in association with natural forest stands that usually contained substantial decayed wood. Birds use decaying wood for cavity nests, winter roost sites, and as a foraging substrate. Approximately 85 species of North American birds use cavities in dead or deteriorating trees (Scott et al. 1977); many of these birds occur in southern pine forests (LeGrand and Hamel 1980). Primary cavity nesters, e.g., woodpeckers, excavate their own nest cavity, mostly in decaying wood (Conner et al. 1975). Many of these cavities are later used as nest and roost sites by secondary cavity nesters. Balda (1975) found secondary cavity nesters composed approximately 50% of the breeding bird population in natural ponderosa pine (Pinus ponderosa) stands that contained substantial decayed wood. In southern forest ecosystems the role of snags and their relationships to birds have not been fully established. This study was designed to investigate the following questions: (1) what birds use snags and in what ways?, (2) can bird density and diversity in early-succession pine stands be i creased by maintaining snags?, and (3) how long do snags stand and how long do birds use them? We thank J. A. Jackson, B. R. McClelland, and V. E. Scott for reviewing a draft of this manuscript and the Southern Timberlands Division of St. Regis Paper Co. for use of their land for this study.