95th ESA Annual Meeting (August 1 -- 6, 2010)

OOS 2 - Another Challenge to Eastern Forests of North America:  Hemlock Wooly Adelgid, Climate Change, and the Loss of Hemlock

Monday, August 2, 2010: 1:30 PM-5:00 PM
303-304, David L Lawrence Convention Center
Charles Goebel
Katherine L. Martin
Charles Goebel
Eastern forests are currently undergoing dramatic shifts in composition, structure, and function as a result of the invasive insect, the hemlock woolly adelgid (Adelges tsugae, HWA). This invasive pest is causing widespread mortality in eastern hemlock (Tsuga canadensis (L.) Carrière). Without any resistance, eastern hemlock is experiencing widespread mortality throughout its range, which extends from the southern Appalachians to the northeast. This disturbance is a particular concern because eastern hemlock has been identified as a foundation species, which defines the ecosystem properties and microclimate of its community, providing habitat for a unique suite of species. As mortality expands, vast areas, including vital riparian forests adjacent to headwater streams, are experiencing large-scale transitions with implications for ecosystem dynamics at fine and landscape scales. These transitions will vary across regions. In particular, current understanding indicates HWA impacts are exacerbated in warmer southern regions with accelerated rates of spread and mortality. In northern areas of New England, the Lake States, and Canada, HWA is thought to be constrained by winter temperatures. However, future climate models indicate that only the northern most areas of hemlock’s US range will experience mimimum winter cold below HWA’s critical threshold. There is also concern that HWA is developing greater cold tolerance at the northern edge of its range. Thus, combining data from forests that across the range and invasion chronosequence will allow development of macro-scale understanding prior to further advancement of the northern front. Our proposed session brings together researchers from across the range of eastern hemlock, from the northeast to the central and southern Appalachians. At the same time, our speaker list combines researchers with years of hemlock data and expertise with investigators who have more recently incorporated HWA-related questions in their research. We have also targeted presentations on scales from tree physiology to remote sensing. The session should serve as a platform for speakers and ESA members to engage in discussion and synthesis of the widespread forest change resulting from HWA. Greater understanding will contribute to improved reality in modeling and contribute to forest management, conservation, and restoration planning. Hemlock mortality is both a regional concern throughout the east, as well as a local concern for Pittsburgh and western Pennsylvania.
1:30 PM
Impacts of eastern hemlock mortality on ecosystem function: A guide to restoration strategies in the southern Appalachians
James M. Vose, Center for Integrated Forest Science; Chelcy R. Ford, USDA Forest Service Southern Research Station; Jennifer D. Knoepp, Coweeta Hydrologic Laboratory; Katherine J. Elliott, Coweeta Hydrologic Laboratory
2:10 PM
Large scale mapping of eastern hemlock
Songlin Fei, Purdue University; Josh Clark, University of Kentucky; Lynne Rieske-Kinney, University of Kentucky
2:30 PM
Responses of eastern hemlock dependent songbirds to hemlock woolly adelgid infestation in Appalachian riparian forests
Terry Master, Department of Biological Sciences, East Stroudsburg University; Michael C. Allen, New Jersey Audubon Society; Jim Sheehan, West Virginia University; Beth A. Swartzentruber, U.S. Department of Agriculture
2:50 PM
Long term monitoring of vegetation and avian communities in hemlock stands
Doug A. Becker, WV Fish & Wildlife Research Unit; Petra B. Wood, West Virginia University; John Perez, National Park Service
3:10 PM
3:40 PM
The rise and fall of eastern hemlock: perspectives from the Northwoods and Appalachia
Michael A. Jenkins, Purdue University; Christopher R. Webster, Michigan Technological University; Eric J. Holzmueller, Southern Illinois University
4:00 PM
Impacts of hemlock woolly adelgid and white tailed deer herbivory on forest invasibility and the abundance of an understory tree species
Anne K. Eschtruth, University of California, Berkeley; John J. Battles, University of California, Berkeley
See more of: Organized Oral Session