B.S. Virginia Polytechnic Institute and State University (1980)
M.S. Virginia Polytechnic Institute and State University (1982)
Ph.D. North Carolina State University (1986)
Quantitative genetics; tree breeding; tropical forestry
Links of Interest
Area(s) of Expertise
- Eucalyptus Amplifolia and Corymbia Torelliana in the Southeastern USA: Genetic Improvement and Potential Uses , FORESTS (2022)
- A genome-wide SNP genotyping resource for tropical pine tree species , MOLECULAR ECOLOGY RESOURCES (2021)
- Genomic Breeding for Diameter Growth and Tolerance to Leptocybe Gall Wasp and Botryosphaeria/Teratosphaeria Fungal Disease Complex in Eucalyptus grandis , FRONTIERS IN PLANT SCIENCE (2021)
- Initial growth results comparing first generation F1 and advanced-generation F2 Pinus patula x Pinus tecunumanii interspecific hybrid families , SOUTHERN FORESTS-A JOURNAL OF FOREST SCIENCE (2021)
- The use of near infrared spectroscopy to predict foliar nutrient levels of hydroponically grown teak seedlings , JOURNAL OF NEAR INFRARED SPECTROSCOPY (2021)
- Comparison of benchtop and handheld near-infrared spectroscopy devices to determine forage nutritive value , CROP SCIENCE (2020)
- Expected benefits of genomic selection for growth and wood quality traits inEucalyptus grandis , TREE GENETICS & GENOMES (2020)
- Growth and modulus of elasticity of pine species and hybrids three years after planting in South Africa , SOUTHERN FORESTS (2020)
- In Situ Genetic Evaluation of European Larch Across Climatic Regions Using Marker-Based Pedigree Reconstruction , FRONTIERS IN GENETICS (2020)
- Estimating realized heritability in panmictic populations , Genetics (2018)
This agreement supports a cooperative project between North Carolina State University and the USDA Forest Service Southern Region for the genetic resource conservation of threatened and endangered tree species in the Southern Region, on the Southern Appalachian forests. Genetic diversity studies are critical in understanding adaptation of imperiled tree species to climate change and forest health impacts. This agreement will allow NCSU, Camcore to identify and add new imperiled tree species to the list for new seed collections. Genetic diversity studies will be done on the species and seeds will be used in restoration efforts on the Southern National Forests.
Located in the heart of Cary, North Carolina, Hemlock Bluffs Nature Preserve is an important ecological, cultural, and recreational resource for the local community. In addition to providing trails and education programs that allow people of all ages to become more familiar with the natural word that surrounds their daily lives, the unique geology of this Piedmont site creates a home for plant species more typical of the mountains of western North Carolina such as galax, and provides refuge for numerous species of reptiles, amphibians, mammals, arachnids, and insects against the ongoing urbanization of Cary. At the center of this unique ecosystem is eastern hemlock (Tsuga canadensis), a tree species known as the ÃƒÂ¢Ã¢â€šÂ¬Ã…â€œredwood of the eastÃƒÂ¢Ã¢â€šÂ¬Ã‚Â that is a canopy dominant species in the forests of the Southern Appalachian, mid-Atlantic, northeastern, and upper mid-western regions of the United States. At Hemlock Bluffs it is a relic of past glacial periods when many northern and mountain tree species survived below glacial margins in the Piedmont and coastal regions of the southeast. As the glaciers retreated many of these tree species migrated to areas now considered to be their natural environments, but the cool, moist environment of the north-facing bluffs along Swift Creek provides a niche where this small population of eastern hemlock is able to survive more than 200 miles distant from its typical habitat. The hemlock woolly adelgid (Adelges tsugae) is an exotic insect from Japan that has caused widespread decline and mortality of eastern hemlock throughout its native range in the eastern United States and threatens the extinction of this keystone forest tree species. Although initial predictions suggested that the isolation of Hemlock Bluffs from the core of the hemlock range would make introduction of this destructive insect unlikely, the adelgid was detected at the preserve in 2010. Since that time, the Town of Cary has worked closely with Bartlett Tree Experts and research and forest health management professionals from North Carolina State University, the North Carolina Forest Service, and the USDA Forest Service to develop a management strategy to limit the impact of the hemlock woolly adelgid at Hemlock Bluffs. So far, the combination of careful adelgid population monitoring and 2 use of chemical insecticides to control the insect when found has worked well. However, much of what we know about the long-term management of this pest comes from research and development activities developed for forests within the core of the eastern hemlock range. Given the unique nature of this Piedmont location and the growing influence of surrounding urbanization, research aimed at developing a better understanding of the genetic and ecosystem processes at this site will allow for the development of management and conservation strategies tailored specifically for Hemlock Bluffs Nature Preserve. This proposal documents three research projects that the Camcore program at North Carolina State University, in collaboration with our university, state, and federal cooperators, feel will aid in improving the long-term sustainability of CaryÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s eastern hemlock resources.
This project will develop and validate a silvicultural tool that improves the health and sustainability of eastern hemlock, an ecologically keystone species in the southern Appalachians threatened by the invasive hemlock woolly adelgid (HWA). Individual or small clusters of "target" trees (i.e., suppressed or intermediate eastern hemlocks with moderate to good crown health) will be released by removing or girdling other stems competing for sunlight directly above and adjacent to the target trees. Increased sunlight is expected to improve hemlock crown health via improved carbon balance, enhanced foliage production, and reduced HWA settlement rates relative to unreleased trees. Treatments will be replicated at a number southern Appalachian sites and will evaluate release by girdling vs. felling and variations on the size of the resulting canopy gap. Operationally, the tool is expected to prolong hemlock health and survival and increase the efficacy of existing HWA management tools (e.g. biological and chemical control) when integrated with them.
The eastern United States is home to some of the most biologically diverse temperate forests in the world that provide a number of ecosystem services including clean air and water, carbon storage, recreational opportunities, and wood and fiber to feed a growing populationÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s need for solid wood and paper products. These critical forest ecosystems are anchored by more than 140 tree species, many of which are threatened by natural and human-caused disturbances including native and exotic insects, diseases, invasive plants, tropical weather systems, wildland fire, development, fragmentation, and climate change (per Forest Tree Genetic Risk Assessment System, Potter and Crane, 2010). As tree populations begin to decline, dynamic approaches to ex situ genetic resource conservation are necessary to secure seed resources for long-term preservation and the eventual restoration of the species and ecosystems. The knowledge gained and materials produced through this agreement will further the mission of the U.S. Forest Service R8 National Forest System Genetic Resource Management Program. It will help to further support the ecosystem health, diversity, sustainability, and productivity philosophy espoused by the U.S. Forest Service. And further, will contribute seed for the restoration of disturbed or degraded forests throughout the eastern United States. The Cooperator will benefit through the strengthening of its genetic resource conservation program, the production of new scientific knowledge, the generation of technical and peer-reviewed publications, and training and education opportunities for students. The objectives accomplished through this agreement will demonstrate that the U.S. Forest Service and Camcore/N.C. State University are leaders in the field of genetic resource conservation of threatened and endangered tree species.
In order to better conserve this rare forest tree species and its ecosystem, an intensive field study can and should be conducted to document the full extent of the Carolina hemlockÃƒÂ¢Ã¢â€šÂ¬Ã¢â€žÂ¢s current distribution, the nature and impact of HWA infestations across that distribution, the efficacy of HWA-targeted insecticide treatments in populations where they have occurred, and how stand structure is responding and will respond to the decline and mortality of Carolina hemlock. The results of this work will be valuable for resource management and conservation organizations by identifying 1) new geographic locations for the species that can be preserved as important future habitat; 2) populations where silvicultural, chemical, and biological control strategies can be implemented to reduce HWA impacts; 3) populations that are most at risk for functional elimination or extirpation for inclusion in ongoing ex situ genetic resource conservation activities; and 4) expected shifts in stand structure and forest management needed to maintain maximum ecosystem function following tree mortality. The results should also serve as a model for designing conservation programs for other rare, isolated tree species whose preferred habitats and forest associations limit the utility of remote sensing.
The ecologically foundational species eastern hemlock, Tsuga canadensis, is being functionally eliminated from southern Appalachian forests by the hemlock woolly adelgid, Adelges tsugae (HWA). This proposal requests funding for the first year of the first Phase of a three-phase project to develop an integrated forest management approach for restoring eastern hemlock to southern Appalachian forests severely impacted by HWA. Overall project summary: Phase 1 (2014-2016): Develop an optimal silvicultural strategy for planting and establishing eastern hemlock seedlings in degraded hemlock stands. Grow eastern and Carolina (Tsuga caroliniana) hemlock seedlings from local-source seed for future phases. Phase 2 (2017-2019): Develop an optimal integrated biological/chemical control strategy on eastern hemlock seedlings established in Phase 1. Use Phase 1 results to establish new, local-source eastern, Carolina, and mixed species (eastern + Carolina) hemlock restoration plots.Phase 3 (2020-2022). Use Phase 2 results to optimize biological/chemical control on local source eastern, Carolina, and mixed species plots. Assess results of all phases on hemlock performance.
Populations of red spruce and Fraser fir in the Southern Appalachian Mountains continue to decline at a high rate, and the restoration of the spruce-fir communities is a matter of concern for numerous scientists and resource managers in the region (Rentch and Schuler 2010). Restoration could increase the extent of these rare forest types and the amount of available habitat for the unique flora and fauna associated with them. Successful restoration will depend upon the availability of a reliable source of high quality red spruce and Fraser fir seed to support breeding and planting activities.
This proposal requests funding for Phase 1 of a three phase project to conserve the genetic resources of rare ash species (Fraxinus spp.) native to the southern region of the United States. Ash species in North America face a significant threat from the emerald ash borer (Agrilus planipennis, EAB), an invasive wood boring beetle native to China that was introduced sometime before 2002 (Herms and McCullough 2014, Ann. Rev. Entomol. 59:13-30). Since its first detection in 2002 in urban forests surrounding Detroit, EAB has spread to 24 US states and 2 Canadian provinces and has killed trees numbering in the tens of millions (Figure 1). Despite significant research and development efforts in chemical and biological control against EAB the invasion continues unabated and its distribution is spreading at an alarming rate. At risk are 16 ash species in North America that at worst face the possibility extinction and at best are likely to realize functional extirpation and significant genetic degradation.The first detections of EAB in the south occurred in 2008, and the pest is now known to occur in six states in the USFS Southern Region (Figure 1). Six ash species occur in the region (Figure 2). Two, green (F. pennsylvanica) and white (F. americana), are widely distributed. Four, Carolina (F. caroliniana), pumpkin (F. profunda), blue (F. quadrangulata), and Texas (F. texensis) have more limited distributions and are considered rare species. Among these blue ash faces the most immediate risk where it is considered a signature species of the Bluegrass and Cumberland Plateau ecosystems of Kentucky and Tennessee where EAB is already widely distributed. The best long-term solution to EAB and the restoration of lost ash forest resources is the breeding and deployment of EAB-resistant planting stock. Significant progress has already been made in understanding the mechanisms and genetic control of EAB resistance in ash species from China, especially Manchurian ash (F. mandshurica), and methods for breeding resistant genotypes through interspecific hybridization and other introgression methods are being investigated (Whitehill et al. 2011. PLosOne 6:9). Key to any resistance breeding and deployment program is access to genetically diverse and broadly adaptable breeding populations of the native ash species to be restored. Given the speed at which EAB continues to spread unabated in North America and the number of trees already killed it is critical that steps be taken immediately to conserve the genetic resources of native ash species so that they are available for future breeding and restoration efforts.
Since 2003, the Camcore program at NC State University has collaborated with the USDA Forest Service Forest Health Protection to design and implement a genetic resource conservation program for eastern and Carolina hemlock, ecologically important tree species native to the eastern United States that face a significant threat from the exotic-invasive insect hemlock woolly adelgid. This program has been funded by USDA Forest Service grants and agreements 03-DG-11083150-850, 05-DG-11083150-210, 06-PA-11083150-002, 09-DG-11083150-008, and 12-DG-11083150-016. Substantial progress has been made during the 13 year funding period covered including the completion of molecular marker studies to describe patterns of genetic structure and diversity across the geographic ranges of both hemlock species, the acquisition of approximately 2.5 million seeds for conservation representing 733 mother trees from 73 populations of eastern hemlock and 134 mother trees from 19 populations of Carolina hemlock, the establishment of conservation seed orchards in Brazil, Chile, and the United States, and the archiving of seed samples from all mother trees for long-term preservation at the USDA ARS National Center for Genetic Resources Preservation in Colorado. Program outputs include 24 peer-reviewed and technical publications and numerous oral and poster presentations at conferences and workshops that provide guidance to researchers worldwide who work towards the conservation of hemlocks and other threatened tree species. The scope of work and objectives listed in this funding request address several final key objectives that will help Camcore and the USDA Forest Service meet goals for hemlock genetic resource conservation and position both agencies to initiate efforts in breeding, seedling production, and deployment towards the restoration of impacted hemlock ecosystems.
Eastern (Tsuga canadensis) and Carolina (Tsuga caroliniana) hemlock are keystone conifer species endemic to eastern North America. Both species face possible extirpation due to the invasive hemlock woolly adelgid (HWA, Adelges tsugae), an exotic insect pest introduced from Japan into the eastern United States in 1951. As part of the larger integrated effort to manage the impacts of HWA on hemlock ecosystems in the eastern United States, since 2003 Camcore (an international tree breeding and conservation program in the Department of Forestry & Environmental Resources at NC State University) and the USDA Forest Service Forest Health protection have collaborated to collect seeds from surviving hemlock populations for the purposes of ex situ gene conservation. The overall goal of the gene conservation effort is to protect against the ?worst-case? scenario where HWA completely eliminates Eastern and Carolina hemlock from eastern forests and maintain viable ex situ populations and seed reserves for breeding and restoration activities. To date, seeds have been collected from 126 mother trees in 18 populations of Carolina hemlock and 407 mother trees in 59 populations of Eastern hemlock (Figure 1), seed samples have been submitted to the USDA Forest Service National Seed Laboratory for long-term preservation, and small conservation plantings have been established in Brazil (Eastern & Carolina hemlock), Chile (Carolina hemlock), and North Carolina (Carolina hemlock). While this represents substantial progress, additional seed collections and ex situ conservation plantings are necessary before we can consider these species successfully conserved. Due to unreliable seed cone production, we are 25 populations short of seed collection goals in the southern US and 7 populations short in the northern US. Additionally, some of our older seed from Carolina hemlock collections made in 2003 is loosing viability in cold storage which may necessitate recollection from some of these sites. Through three decades of forest genetic resource conservation work around the world, Camcore has determined that a population is considered conserved ex situ when it is represented by at least 10 open-pollinated families (family = seeds collected from an individual mother tree) and 5 individuals per family replicated on multiple sites. To meet this target, current hemlock conservation plantings need to be expanded and new plantings need to be established inside and outside of the United States. Continuing seed collections and expanding the ex situ conservation planting program for Eastern and Carolina hemlock are the objectives of this grant proposal.