successes--our major accomplishments
Forest Ecosystem Restoration and Management

SRS Research Instrumental in Sequencing Poplar Genome

Nurul Faridi (979-862-3908)
nfaridi@fs.fed.us

Identifying and mapping the chromosomes of trees using genetic markers and genes is a part of the ongoing multi-agency National Science Foundation Plant Genome Project. With its relatively small genome and 19 pairs of chromosomes, poplar has been considered a model species for forest tree genetics and genome research. The poplar genome was recently sequenced using the shotgun method, where the genome is broken up and random pieces of DNA then sequenced. These short pieces are then put back together into longer pieces based on the overlapping sequences of the various pieces. When the genome is fully sequenced, there will 19 separate DNA sequences, one for each chromosome. However, the current the current genome sequence (called the assembly) still contains 2,447 sequences (called scaffolds), suggesting that a complete genome sequence has not been realized.

SRS research geneticists are involved in physically locating and validating the hypothesized positions of the scaffolds using a molecular cytology technique called fluorescence in situ hybridization (FISH). Initial studies have found that FISH can reliably validate scaffold positions, and will certainly play an important role in completing the genome sequence that will provide an invaluable tool for cloning poplar trees with economically and ecologically important genes.
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Method to Evaluate Upland Hardwood Forests

Henry McNabb (828-667-5261, x119)
hmcnab@fs.fed.us

Conventional methods for determining forest site quality that use tree age and height relationships are laborious to apply and often provide inaccurate estimates when used in upland oak forests. Alternative techniques based on tree species composition are well suited for forest management planning and are easily combined with routine stand examination inventories. For example, a composition-based classification system has been developed for the Southern Appalachian Mountains of western North Carolina by ranking all tree species in relation to their relative moisture requirements and assigning an index value to each species. In FY 2006, this approach was expanded to include the Cumberland Plateau, with additional species present in upland hardwood forests of northeastern Kentucky added to the classification system.

Tests of this expanded system were conducted on the Morehead District of the Daniel Boone National Forest and suggest that the species composition method of site classification provides a quantitative method for assessing the environmental moisture regime of forest stands. Forest managers can easily and economically apply the system using inventory data by determining all tree species present in a stand and calculating a moisture index for the stand based on the relative moisture values for each species. Ongoing work will determine if the species composition method of site classification can be used to assess the fertility of a stand, a site characteristic that is important for some tree species such as white ash and sugar maple.

The species composition method of site classification will be particularly useful to county service and Extension foresters working with landowners who have little knowledge of forestry, since this method of classifying the ability of the site to grow trees is intuitive, easily applied, repeatable, and requires only an ability to identify tree species. .
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Can Silviculture Stave Off the Effects of Exotic Pests on Forest Health?

Callie Schweitzer (256-372-4230)
cschweitzer@fs.fed.us

SRS researchers are evaluating silvicultural treatments currently used by the Daniel Boone National Forest, KY in relation to impending infestations by gypsy moth and the related disease complex, oak decline. They are looking at four treatments: (1) shelterwood harvest, with reserves that result in two-aged stands; (2) oak shelterwood, harvests that retain a medium level of overstory density to enhance oak regeneration; (3) thinnings to reduce stand density; and (4) oak woodland, a combination of thinning to create open habitats with prescribed burns to maintain this condition. Each silvicultural treatment, matched with an untreated control, will be replicated across the two most common site types on the Daniel Boone National Forest.

This large-scale research project promotes collaboration among partners, allowing SRS researchers to ask a range of scientific questions. Collaborators are studying wildlife (including the endangered Indiana bat), stand dynamics using dendrochronology (i.e., the study of tree-rings), the relationships between light and vegetation response, forest harvesting operations, and the potential for using wood from silvicultural operations as biofuel. The results of this study will improve predictions of how tree species respond to silvicultural treatments, and provide information to managers on silviculture prescriptions needed to improve oak regeneration, harvesting operations needed to reduce impacts to soil, and prescribed burning prescriptions needed to create sustainable oak woodland conditions.

Research results will be used to adjust how silvicultural prescriptions are applied on the Daniel Boone National Forest. The research sites will be used as demonstration areas where both the general public and private forest landowners (and managers) can see these silvicultural treatments and how the vegetation responds over time. University of Kentucky Extension personnel and other groups can utilize the demonstration areas for educational programs and tours to influence land management practices on non-federal lands.
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Impacts on Neotropical Migratory Birds from Logging Southern Appalachian Hardwood Forests

Kay Franzreb (865-974-0932)
kfranzreb@fs.fed.us

Studies of Neotropical migratory birds (birds that migrate between the United States and Central and South America) have found declines in both distribution and overall population numbers in Southeast, where they have been tied to habitat fragmentation in breeding grounds and to deforestation of the over-wintering areas. Habitat fragmentation has resulted from a variety of land management practices, including timber harvesting.

SRS scientists and cooperators compared both the density and diversity of Neotropical migratory bird species following timber harvesting in cove hardwood forests in the Southern Appalachian Mountains of North Carolina. Study areas were 4 to 103 years old, had undergone clear-cutting or selective tree removal, and represented four successional stages (early, sapling/pole, mid, and late). Neotropical migrants made up between 60-69 percent of the bird species in these areas in spring, and made up a large proportion of the breeding bird pairs found. Late successional cove hardwood stands had a more diverse bird fauna (especially Neotropical migrants) than sapling/pole or mid-successional forests. Neotropical migrants comprised 70 percent or more of the birds in each successional class.

One goal of the Forest Service forest management plans for parts of the Southern Appalachians is to “provide breeding, wintering, and migration staging and stop-over habitat for migratory birds in ways that contribute to their long-term conservation.” To provide suitable quality breeding habitat for all Neotropical migrants will require a variety of management strategies, possibly including various forms of timber harvesting in areas where such harvesting has not occurred in recent years. Logging would provide early successional habitats for species that prefer disturbed forests, such as the golden-winged warbler. Timber harvesting may be useful for other early successional bird species if sufficient tree removal is undertaken. Likewise, some stands should be maintained in relatively undisturbed condition for those species that are more common in older, mature habitats.
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Genes Hold Key to Biological Control of Chestnut Blight

Tom Kubisiak (228-832-2747, x213)
tkubisiak@fs.fed.us

Cryphonectria parasitica is the fungal plant pathogen that causes chestnut blight. The introduction of C. parasitica from Asia into North America in the early 1900s resulted in the death of billions of American chestnut trees in what is still often referred to as one of the worst ecological disasters in U.S. history.
Since 1995, SRS scientists have been working with The American Chestnut Foundation to restore the American chestnut to the Eastern United States by breeding blight-resistant trees. The greatest barrier to restoration is the fact that the chestnut blight fungus remains active in forest soils throughout the former range of the tree, and kills chestnut seedlings before they can mature.

To help address this issue, SRS scientists are studying C. parasitica at the genetic level. Interestingly, C. parasitica is prone to infection by double-stranded RNA viruses called hypoviruses, which reduce the virulence and fitness of the pathogen and exert strong biological control of chestnut blight in some populations, particularly in Europe. In natural populations, the fusion of cells from individuals of C. parasitica that differ at one or more genes named vegetative incompatibility (vic) genes triggers programmed cell death (pcd). A significant correlation exists between the rate of pcd and the probability of viruses being transmitted between incompatible individuals. To better understand the role that vic genes play in virus transmission, it would be advantageous to have the DNA sequence of the vic genes.

Scientists at the SRS genetics unit recently developed a molecular marker map for C. parasitica, identifying several markers that are tightly linked to the vic genes. This is the first step in isolating and sequencing these genes. Once these genes have been isolated and sequenced, evolutionary studies on the development of this viral defense mechanism in C. parasitica will be possible, providing new targets for biological control methods. 
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Research to Support Wildlife Conservation Planning on the Cumberland Plateau

Callie Schweitzer (256-372-4230)
cschweitzer@fs.fed.us

Upland hardwood researchers based in the Cumberland Plateau region are participating in three large-scale studies on the effects of forest management on wildlife, designed to: (1) examine how habitats change after disturbances; (2) determine how communities of birds, mammals, reptiles, and amphibians respond to small localized changes in temperature and moisture; (3) determine the effects of forest disturbance on food available to wildlife and diet choices; (4) determine effects of forest disturbance on amphibians that breed in ephemeral ponds; and (5) examine how communities of birds, mammals, reptiles, and amphibians change over time in response to changes in the structure of their habitats.

The research builds on an existing large-scale study in Jackson County, AL, where SRS researchers study how forest harvesting affects the diversity of birds, reptiles, and amphibians in the area. A sister study was set up on the Bankhead National Forest to look at the response of reptile, amphibian, and bird communities to thinning and burning treatments?with special emphasis on the copperhead snake and on the cerulean warbler, a species of concern. With more information about cerulean warbler populations, researchers can develop models based on habitat and landscape characteristics to predict where the birds will most likely be found.

These large-scale, multi-disciplinary studies allow scientists to determine how habitats and microclimates within a forest stand are influenced by disturbance and changes in stand structure. They allow silvicultural researchers to test how forest management can change vegetation structure and composition over time and how these changes affect the animals that live there. Recognition of factors that affect animal population fluctuations will help natural resource managers develop plans that address these factors in conjunction with other forest management goals.
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Forest Bat Habitats in South Carolina

Susan Loeb (864-656-4865)
sloeb@fs.fed.us

Despite the high number of endangered and sensitive bats in the Southeast, few studies of forest bat habitat use have been conducted in the region. To meet habitat requirements for bats, forest managers need information on the most important factors determining bat habitat use.

During 2004 and 2005, SRS researchers placed Anabat II bat detectors at 109 points located in three forest types and three age classes in the Sumter National Forest to identify important factors influencing bat habitat use in northwestern South Carolina. They were particularly interested in three factors: vegetation density at the local scale, forest age class and composition at the stand scale, and distance to streams and roads at the landscape scale. Because habitat use by bats often varies among species depending on their body size, wing morphology, foraging mode, and echolocation call structure, researchers also examined how individual species responded to habitat factors at each of the spatial scales.

They found that vegetation density was the best predictor of overall bat activity; bats were more commonly recorded at points with sparse vegetation than at points with medium or dense vegetation. Age class was also a good predictor of bat habitat use; bats were most likely to be recorded in early successional stands and least likely to be recorded in mid-successional stands. Habitat use by individual species was also strongly influenced by vegetation density surrounding the detector. Big brown bats, red bats, eastern pipistrelles, and northern long-eared bats were most commonly found in areas with sparse vegetation. Age class was also an important factor in eastern pipistrelle and northern long-eared bat habitat use. Pipistrelles were more likely to be recorded in early successional stands, whereas northern long-eared bats were recorded almost exclusively in mature stands. No landscape factors proved to be important in predicting overall or individual species’ habitat use.
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Managing Midstory Vegetation with a Combination of Treatments

Dale Brockway (334-826-8700)
dbrockway@fs.fed.us

A SRS study conducted at Fort Benning, GA, is examining the effects of midstory reduction efforts on the health of longleaf pine forests. Early results suggest that stand thinning by mechanical shredding of woody plants is an effective way to rapidly alter forest structure. This type of thinning reduces the risk of forming midstory “fire ladders” that carry fire into overstory trees; this vegetation layer is instead shredded into woody debris that can be safely burned by ground fires. However, the rapid regrowth of mechanically-treated vegetation means that timely follow-up with periodic prescribed burning is required to maintain the generally open structure of such rehabilitated forests and further abate the wildfire hazard posed by the threat of midstory regrowth.

In a fire study in Florida, researchers observed that saw-palmetto (Seronoa repens) comprised the principal and most dangerous understory and midstory fuel in that ecosystem, and that it could not be effectively reduced by fire-only treatments only with fire. Prescribed burning must be followed by some type of mechanical treatment (i.e., roller-chopping or mowing) to reduce the dominance of palmetto and reduce the risk of wildfire. In a similar study in Alabama, SRS researchers found that several of the hardwood tree and shrub species in the midstory are best controlled by mechanical treatment followed by repeated prescribed fires. Mechanical treatment alone is an insufficient remedy because of rapid regrowth; at the same time, using fire alone is a very slow remedy, sometimes requiring several decades to transcend the key ecological thresholds for restoration.
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Oak Regeneration Problems in the Ozark Highlands

James Guldin (870-723-1623)
jguldin@fs.fed.us

The oak forests of the Ozark Highlands, one of the region’s greatest and most highly treasured resources, are not regenerating themselves. Oaks are being replaced by more shade-tolerant, less desirable species. Regenerating oak species is particularly complex because the process is affected by a broad set of factors.

In FY 2006, SRS researchers made a number of contributions to understanding and resolving this problem. First, they published a paper describing regeneration across a typical forest landscape in the Ozark Highlands that showed that the regeneration of desirable species (both oak and pine) was abundant on the drier, rigdetop sites, which were too harsh to support intense competition from other species. In contrast, little desirable regeneration occurred on the better sites (hollows and lower slopes), indicating that these sites will require more aggressive silvicultural measures to obtain successful regeneration.

A second publication reported on the disturbance histories of the oak stands occurring on better sites where it is difficult to regenerate oaks. Clearly, favorable conditions existed at the time the current oak forests originated. What conditions were different that allowed oaks to regenerate at that time compared with today? SRS researchers were able to reconstruct the disturbance histories of these stands to show that frequent disturbances (tree removals and low-intensity fires) produced conditions that were favorable to oak regeneration. The disturbances that allowed understory oaks to persist also suppressed the development of shade-tolerant, fire-susceptible competitors. This research indicates that prescribed fire may play a critical role in achieving successful oak regeneration, a conclusion supported by a third publication that showed that oaks can withstand damage from prescribed fire far better than their competitors. Damage to oak seedlings from two prescribed fires was only 6 percent compared to about 90 percent for competitors.
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Oak Decline and Red Oak Borer Effects in the Interior Highlands

James Guldin (870-723-1623)
jguldin@fs.fed.us

Forests of the Interior Highlands of Arkansas, Oklahoma, and Missouri are being affected by oak decline and an unprecedented outbreak of a native beetle called the red oak borer. The SRS unit in Arkansas has been at the forefront in detecting, monitoring, and resolving this serious forest health event, as shown by the recent publication of three papers that summarize findings to date.

Groundtruth assessments show that oak decline and red oak borer are found throughout the Interior Highlands, not just in a few areas, as was initially thought. Across the region, about 30 percent of red oaks are affected, with damage found across all size classes. By comparison, only about 10 percent of white oaks are affected, with damage concentrated only in the smallest and largest diameter classes. An analysis of site conditions across the region suggests that other factors, such as the physiological condition of individual trees, may be a more important determinant of whether a given tree is affected by oak decline.

SRS scientists developed a tool called the Forest Health Quotient?calculated as the ratio of standing dead trees to live trees? to make early predictions of decline in forest health in this forest type and region. In the oak-hickory forest type of the Interior Highlands, they found that if the Forest Health Quotient exceeds the regional average of 0.09, problems with forest health may well be present. The variables used to calculate the Forest Health Quotient are readily available from data regularly collected in the 13 Southern States as part of the ongoing work by the SRS Forest Inventory and Analysis unit, and the new measure could be used to develop an early warning system for forest health in any region of the country.
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Small Mammal Responses to Alternative Pine Regeneration Treatments

Ron Thill (936-569-7981)
rthill@fs.fed.us

As part of a study of forest management treatments started on the Ouachita National Forest in 1991, SRS scientists monitored small mammal populations in stands where four regeneration treatments were applied--single-tree selection, group selection, shelterwood, and clear-cutting--and compared these to small mammal populations in unharvested controls.

Small mammal populations were monitored in 20 forest stands two years before harvesting, then 1.5, 3.5, and 5.5 years after harvesting. Of the 20 stands, four were treated with each of the four different forest management options, plus an unharvested control. Before harvest, all stands had sparse understory vegetation and high basal areas (BA), indicating a thick growth of trees. Researchers had very low capture rates in these areas pre-harvest. After harvest, capture rates for all species of small mammals were significantly higher, regardless of the harvest method was used, with five-fold increases in capture rates just 1.5 years after harvest.

Some species were captured more frequently in stands harvested in a specific way or with certain vegetation characteristics. For example, fulvous harvest mice were most frequently captured in clearcuts. These mice, along with cotton rats and pine voles, seemed to prefer stands with abundant herbaceous understory vegetation and low BA. Eastern woodrats, golden mice, and white-footed mice were associated with moderate to dense woody vegetation in the understory and intermediate BA levels. None of the small mammal species was captured exclusively in unharvested stands; most taxa captured appear to tolerate disturbances from timber harvest.
The reduced BA and disturbance associated with any of the four timber harvest treatments tend to create habitats that are attractive to small mammals. Increases in understory herbaceous and woody vegetation, down wood and logs, and soft mast were accompanied by increases in overall numbers of small mammals. Even the less intense regeneration methods such as group selection resulted in significant increases in small-mammal abundance.
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How Tree Roots Affect Forest Soils

James Guldin (870-723-1623)
jguldin@fs.fed.us

A better understanding of the interactions between trees and forest soils is necessary to effectively manage and enhance forests at the landscape scale. Two recent research products provide important new insights into how trees affect soils and vice versa. A journal article co-authored by a SRS scientist and a university cooperator reports on the physical displacement of soils by tree roots when trees are blown over and uprooted. The researchers found that the displacement characteristics of pine and hardwoods differed; hardwoods promoted more lateral displacement, while pines had a pronounced vertical displacement associated with mounding around the base of the fallen tree. Research showed that displacement, stump holes, and uprooting helped maintain a continuously mixed soil, and may be the cause of the the high variability in soil characteristics common in forest soils of the Mid-South.

A Ph.D. dissertation funded by the Station investigated the long-term effects of converting forest cover to grasslands on the movement of water and sediment in a limestone terrain. Grasses promoted a larger volume of lateral water movement in the upper soil, while tree roots encouraged greater movement of water deeper within the soil profile. This research showed that land management decisions in limestone terrain should consider slope, soil depth, and drainage condition. The study also demonstrated that forests are critical to soil retention on steep slopes, where the plant communities associated with forest trees provide additional tree and grass roots.
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Restoring Longleaf Pine to Declining Loblolly Stands

Joan Walker (864-656-4822)
joanwalker@fs.fed.us

Across the Southeast, land managers are challenged to restore longleaf pine forests to support red-cockaded woodpeckers and associated species of concern, while retaining critical habitat features, including mature trees. At some locations, managers need protocols to restore longleaf pine on sites while still retaining some other large pine trees in the canopy.

At Fort Benning, GA, nearly three-quarters of the active red-cockaded woodpecker cavities are located in mature loblolly pine stands in which trees are dying at an alarming rate. “Loblolly decline,” as it has been called, may be the result of several stressors including disease, environmental conditions, and possibly management activities. Because such stressors are not uniformly distributed on landscapes, managers need models to help predict which stands are most vulnerable to decline. In the most vulnerable stands, restoration protocols will likely require the removal of some canopy pines; managers need guidance for selecting individual trees for removal, ideally leaving trees likely to live the longest.

A team of researchers led by a SRS scientist received funding from the Department of Defense for a series of studies to address these management needs, specifically to develop protocols for restoring longleaf pines to stands currently occupied by declining loblolly pines. The researchers will also develop a model to predict which stands are most vulnerable to loblolly decline and provide management recommendations for these stands. They will also develop a model to forecast the mortality of individual trees within stands to provide guidance for individual tree removals.

Field experiments will be conducted at Fort Benning, GA, and at Camp Lejeune, NC. At both these sites, loblolly pines have been planted on sites that were historically longleaf pine forests, but under very different environmental conditions. Establishing the same experiment at two different sites will provide information needed to extrapolate findings across the range of longleaf pine habitats in the region.
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Longleaf Pine Root System Development

Susana Sung (318-473-7233)
ssung@fs.fed.us

he demand for longleaf pine seedlings continues to increase, but tree nurseries have problems producing uniform high quality seedlings in the large numbers needed. As a result, container longleaf pine planting stock varies widely in both production quality and size; widespread planting of variable quality longleaf planting stock has led to many sapling longleaf trees being blown down by wind storms (windthrow). To date, there has been too little effort to understand how this variable quality in planting stock has affected the field success of outplanted seedlings.

In FY 2006, SRS researchers began a study to examine the problem of windthrow in sapling longleaf pine plantations thought to be related to the variation in container-stock size and quality. Early results suggest that container size influences the survival of seedlings over time, with seedlings grown in larger containers being hardier after planting than those grown in smaller containers. Longleaf pine seedlings grown in copper-treated containers survive better than seedlings grown in untreated containers. These preliminary results will be presented to forestry professionals at the 14th Biennial Southern Silvicultural Research Conference in February 2007. Future research will include tests of the wind firmness of these trees.

The Longleaf Alliance is especially interested in the outcome of this research as these findings could affect longleaf management across the Southern Region on both private and public lands. Without some assurance that seedlings are ready for outplanting and have a high probability of long-term survival, forest landowners could become discouraged in their efforts to restore acres to longleaf pine.
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How Long Can Pine Snags Stand?

Dan Saenz (936-569-7981)
dsaenz@fs.fed.us

Habitat for cavity-nesting wildlife such as the endangered red-cockaded woodpecker is closely tied to the availability of standing dead trees (snags). Large snags are particularly important because they provide possible habitat for both large and small cavity excavators. Because it has been assumed that they decay and fall to the ground quickly in the hot, humid conditions of the Southeast, pine snags have been historically seen as having little value for cavity nesters.

SRS scientists studied the longevity of large pine snags in eastern Texas over a 20-year period, recording data during annual surveys of red-cockaded woodpecker cavity-tree clusters. The researchers checked the status and height of all red-cockaded woodpecker cavity trees that died, determining the cause of death and tree species of a total of 136 cavity tree snags. The height of each snag was monitored annually until it was less than 1 m in height. Five years after tree death, 92 snags (67.6 percent) were still standing and averaged 13.9 m in height. Ten years after tree death, 21 snags (15.4 percent) were still standing and averaged 10.0 m in height. After 15 years, 4 snags (2.9 percent) averaging 5.3 m in height still remained standing. Two snags (1.5 percent) averaging 2.7 m in height survived through 19 years but had fallen by the end of the 20th year.

Study results showed that pines killed by wind snap at mid-bole survived longer as snags than those killed by bark beetles. Longleaf pine snags remained standing significantly longer than loblolly pine snags, but not longer than shortleaf pine snags. This research shows that larger pine snags should be recognized as a long-term component of the ecosystem that can provide wildlife habitat long after the trees die. This important role of large pine snags as wildlife habitat is especially true for longleaf pines and pines killed from wind snap.
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Ecology of the Louisiana Pine Snake

Craig Rudolph (936-569-7981)
crudolph01@fs.fed.us

SRS scientists and cooperators have been investigating the ecology, status, and management of the Louisiana pine snake (Pituophis ruthveni), one of the rarest vertebrates in the United States, for more than a decade. The Louisiana pine snake is highly vulnerable to extinction due to its dependence on fire-maintained ecosystems. Very little is known about the basic ecology of the species, and how land managers can reduce or mitigate adverse impacts on its habitat.

SRS scientists recently published two articles reporting on the results of a Louisiana pine snake telemetry study. The first described the interaction of Louisiana pine snakes and temperature, an important determinant of habitat use of many reptiles; the second assessed habitat use and movement patterns of wild and captive-bred Louisiana pine snakes. In addition to providing critical data on habitat use and movement patterns needed to determine appropriate habitat management practices and the size of management areas needed to support Louisiana pine snakes, this research provides insight into the feasibility of reintroducing captive-bred snakes to vacant habitat.

Ongoing SRS research on Louisiana pine snakes informs future conservation measures for this critically imperiled species. The Louisiana pine snake has been designated as a Candidate Species under the Endangered Species Act, and has received increased attention from the Forest Service, the Department of Defense, and the major timber companies who manage much of the forest land within this species’ range. An annual meeting of stakeholders is held to exchange information concerning the biology and management of the species. An improved understanding of the biology and management of Louisiana pine snakes will allow biologists and managers to better manage and restore the critically imperiled longleaf pine ecosystem.
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Chilling Effect

Kurt Johnsen (919-549-4012)
kjohnsen@fs.fed.us

After centuries of forestry, the simple aboveground growth of trees is now reasonably easy to predict. Today’s researchers and managers, operating in a time of changing climate and forest management practices, need more information about what happens below ground to accurately predict growth. How do biological processes like photosynthesis affect the movement of carbon in forest trees and how does this affect tree growth? How much of this carbon gained through photosynthesis goes below ground? How can this belowground carbon be manipulated? These questions are more difficult to answer because belowground research is difficult and often destructive.

SRS researchers have developed a method to quantify the amount of carbon that goes below ground by chilling the stem of the tree. Their chilling treatment only lasts for two days, but this is enough time to provide critical information on carbon movement and appears to cause no injury to the tree, unlike other methods to estimate belowground carbon. The science team plans to use this new technique to quantify seasonal differences in belowground carbon flow and to assess the impacts of environmental variation (air and soil temperature, relative humidity, soil moisture) on carbon movement. Data from these studies will be used to improve already existing process-based models, and will enable researchers to provide better predictions on forest growth and function in changing environments, and provide the basis for developing simple models for estimating carbon credits. This research has the potential to help policy makers, institutions, and individuals interested in carbon sequestration, tree growth, and carbon credits.
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Physiological Effects of Prescribed Fire in Longleaf Pine Stands

Mary Anne Sword Sayer (318-473-7275)
msword@fs.fed.us

Long-term studies of the effects of prescribed fire in longleaf pine stands have been conducted in central Louisiana on the Palustris Experimental Forest and Kisatchie National Forest for over 80 years. Study plots include longleaf pine forests that range in size from seedlings to large poles. Prescribed fire is used on some of these stands on a regular basis, while other stands are protected from all fires. Over the years, these paired treatments have provided an excellent setting to investigate the growth, physiology, and soil responses of longleaf pine stands to fire and to examine how fire can be used to promote the sustainability of these systems.

One aspect SRS researchers are studying is how prescribed fire changes the physical and chemical properties of the soil and the longleaf pine forests they support over time. The results from this study will be used to determine if long-term, repeated prescribed burning reduces the quality of western Gulf Coastal Plain soils and their ability to grow longleaf pines. Other studies on the effect of biennial prescribed burning on longleaf saplings are in their fourth and final year. Results from this study will provide insights into how these young pines compensate for fire-induced damage to their foliage.
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Resin Discharge and Resistance to Southern Pine Beetle

Jim Roberds (228-832-2747, x211)
jroberds@fs.fed.us

The southern pine beetle is the most destructive insect pest of pines in the Southeastern United States. Individual pine trees that discharge large quantities of oleoresin (resin) when wounded are considered to be most resistant to attack by this aggressive bark beetle. Resin production capacity is assessed by making small surface cuts into the tree trunk at breast height and then measuring resin flow; managers need to know how many of these measurements to take on any one tree to provide a proper assessment. Answers to this and other related questions can be found by studying this characteristic’s repeatability, a measure of trait consistency within individuals. To provide this information, SRS researchers estimated repeatability values for resin yield in three different species of southern pine: loblolly, longleaf, and slash.

In general, the repeatability estimates they came up with were considerably greater than 0.5, indicating that variation among trees is somewhat larger than variation within trees (i.e., among values assessed on the same tree). Such repeatability implies that, for most uses, the average of two assessments per tree provides an adequate estimate of tree resin yield at breast height. Prior to this research, the number of measurements needed to properly evaluate tree yields in the southern pines was unknown. Results of this research are of interest to research entomologists and geneticists, tree breeders, forest health specialists, State forestry professionals and consulting foresters for use in properly evaluating a tree’s potential, relative resistance level to southern pine beetle attack.
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Other Significant Accomplishments

Contributed chapters to the recently published Longleaf Pine Ecosystems: Ecology, Silviculture and Restoration, including chapters on longleaf pine regeneration ecology and methods; growth and yield model; and other research topics.

Developed a cytomolecular map for loblolly pine, the first of its kind for any conifer.

With faculty at Auburn University, conducted two siliviculture training workshops for the Florida Division of Forestry staff on the field application of longleaf pine regeneration techniques developed by the Station.

Assessed population trends in endangered red-cockaded woodpeckers in east Texas, and determined the impacts of rainfall and the El Niño climate pattern on the birds.

Initiated a study to assess the effects of atmospheric pollution on high elevation bird and snail communities in the Southern Appalachians.

Completed the third year of Department of Defense funded research on the Louisiana pine snake at Fort Polk,LA.

Completed a feasibility study on the use of stable isotope analysis to determine migratory patterns of the endangered Indiana bat; preliminary analysis suggests that this technique may be an effective new tool for identifying factors causing declines in the species.

Provided the National Park Service with a comprehensive report on the bat communities of the Chattahoochee River National Recreation Area, Congaree National Park, Fort Pulaski National Monument, Fort Sumter National Monument, and Ocmulgee National Monument.

Quantified the impact of a major ice storm on current future carbon storage.

Completed measurement work on a long-term study on the effects of litter retention, herbicide applications, and fertilization on loblolly pine growth and yield and forest soil and plant productivity.

Completed a study of white oak acorn quality in relation to germination and seedling growth relative to efforts to regenerate oak forest for wildlife and timber.

Completed seventh year of data collection on wild leek populations in 21 permanent sites in North Carolina. Data will be used to develop a monitoring plan that will be implemented by the National Forests of North Carolina.
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Partnership Highlight

Southeastern Bat Blitz

Susan Loeb (864-656-4865)
sloeb@fs.fed.us

SRS researchers co-hosted the 5th Annual Southeastern Bat Diversity Network Bat Blitz near Mountain Rest, SC; the survey covered areas of northeastern South Carolina and northwestern Georgia. Over 60 participants surveyed parts of the Sumter and Chattahoochee National Forests, as well as on State and private lands.

The bat blitz involved intense surveys—three nights of mist netting on 30-40 different sites, acoustic sampling, and other techniques—to look at species composition and prevalence of bats on parts of the Sumter and Chattahoochee National Forests and adjoining State lands. The event also provided an opportunity for researchers, management biologists, and students from Federal and State agencies, universities, and industry to exchange information and develop strategies for studying bat communities. Event leaders also trained students and biologists on techniques for catching bats, recording information, and sampling for genetic and isotope studies.

The event was hosted jointly by SRS, the Francis Marion and Sumter National Forests, the Chattahoochee National Forest, and the South Carolina and Georgia Departments of Natural Resources.
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Key International Activities

Jim Guldin gave an invited keynote presentation for the IUFRO Uneven-Aged Silviculture Working Group in May 2006 in Quebec, Canada.

Dana Nelson gave an invited presentation at an IUFRO meeting in Pretoria, South Africa.

Martin Spetich gave an invited presentation at the International Workshop on Forest Modeling in Beijing, China, in June 2006.

Jerry Michael presented an invited global perspective on the use of forestry herbicides and their impact on soil microbes and aquatic organisms to a select group of scientists from the European Union at an international meeting in Ireland.
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Awards

The Southern Forest Nursery Association presented a Lifetime Achievement award to James P. Barnett in recognition of his vision and leadership in forest regeneration.

Richard Conner received the Wings Across the Americas award from the USFS Washington Office for his participation in establishing the Red-cockaded Woodpecker Recovery Translocation Cooperative.

Dan Saenz received the SRS Director’s Early Career Scientist Award in recognition of exceptional scientific productivity, distinguished teamwork, and outstanding potential for future achievement.
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