Monday, August 4, 2008: 1:30 PM-5:00 PM
202 D, Midwest Airlines Center
OOS 3 - Insect Disturbance Ecology: A Forest's Perspective
Insect outbreaks annually affect more forest area in temperate and boreal North America than harvesting and wildfire combined. However, the long-term costs and ecosystem consequences of insect outbreaks on forest health and productivity are difficult to quantify, because of the variety of pests involved, the varying scale and severity of the impacts, and the variability in system response to those impacts across geographic regions. Impacts to host species can vary from simple growth reduction to widespread mortality at spatial scales ranging from single trees to entire regions. Resulting changes in wind and light exposure can lead to divergent responses of non host species, varying from increased mortality to growth release. The nonlinear and multi-scaled nature of insect disturbance further limits our ability to forecast ecosystem change in response to outbreak activity. These challenges are underscored by the fact that empirical risk assessments for insect outbreaks typically have low explanatory power and limited spatial domains of applicability, implying that local details and system context are important. Synthesis is needed to better understand and project the short- and long-term consequences of insect disturbance as it influences forest structure and function. Cross-system comparisons should also provide insight into novel responses of forests to insect disturbances within the context of changing climate and land use. This symposium will compare and contrast a suite of otherwise unrelated studies to understand how forests respond to insect outbreaks across pest species, geographic locations, and scales. Presentations are organized to allow comparison among these different factors. For example, we will contrast studies from both the core and fringes of a pest species’ geographic range to begin to tease apart the confounding influences of climate and tree species composition on forest response to outbreaks. Our examples draw primarily from defoliator and bark beetle systems in North America, and include results from both recent studies and new analyses of past datasets. A paper targeting climate effects on biotic disturbances provides the context rather than the theme for the symposium (i.e., one of the main drivers underscoring the need for synthesis). We will conclude with a review and discussion of the papers presented to seek the commonalities and differences among the different insect pest systems and geographic locations in terms of disturbance patterns and their effects on forest productivity and succession.
Organizer:Brian R. Sturtevant, U.S. Forest Service
Moderator:Brian R. Sturtevant, U.S. Forest Service
1:30 PMSpruce budworm disturbance patterns in Eastern Canada
David A. MacLean, University of New Brunswick
1:50 PMManagement legacies and spruce budworm host patterns in Minnesota and adjacent Ontario
Patrick M.A. James, University of Toronto, Brian R. Sturtevant, U.S. Forest Service, Philip A. Townsend, University of Wisconsin-Madison, Marie-Josée Fortin, University of Toronto
2:10 PMForest tent caterpillar disturbance: The importance of extreme events
Barry Cooke, Canadian Forest Service
2:30 PMSuccessional responses of aspen forests to successive FTC Outbreaks in northeastern Ontario
Rongzhou Man, Ontario Ministry of Natural Resources, Taylor Scarr, Ontario Ministry of Natural Resources, James A. Rice, Ontario Ministry of Natural Resources
2:50 PMBiological legacies and seedling bank dynamics of a spruce beetle-killed Engelmann spruce landscape
R. Justin DeRose, Utah State University, James N. Long, Utah State University
3:10 PMBreak
3:20 PMMountain Pine Beetle disturbance in Yellowstone National Park
Paul R. Moorcroft, Harvard University, Heather J. Lynch, University of Maryland, Roy Renkin, Yellowstone Center for Resources, Robert Crabtree, Yellowstone Ecosystem Research Center
3:40 PMHow fast will the trees die? Modeling ash (Fraxinus spp.) decline in forest stands infested by emerald ash borer (Agrilus planipennis)
Kathleen S. Knight, US Forest Service Northern Research Station, Robert P. Long, US Forest Service Northern Research Station, Daniel A. Yaussy, US Forest Service Northern Research Station, Joanne Rebbeck, US Forest Service Northern Research Station, Annemarie Smith, Department of Natural Resources, Kamal Gandhi, Ohio State University, Daniel A. Herms, Ohio State University
4:00 PMA review and synthesis of multispecies growth suppression and mortality responses to forest canopy defoliator outbreaks
Jane R. Foster, University of Wisconsin-Madison, David J. Mladenoff, University of Wisconsin-Madison
4:20 PMPatterns of biotic disturbance with respect to spatiotemporal variation in climate
Matthew P. Ayres, Dartmouth College
4:40 PMSynthesis of insect disturbance from a forest's perspective
Daniel Kneeshaw, University of Quebec at Montreal, Enrique Doblas-Miranda, University of Quebec at Montreal, Brian R. Sturtevant, U.S. Forest Service, Phil Burton, University of Northern British Columbia, Canadian Forest Service, Marie-Josee Fortin, University of Toronto, David MacLean, University of New Brusnwick, Barry Cooke, Canadian Forest Service, Rongzhou Man, Ontario Ministry of Natural Resources, Patrick James, University of Toronto, Josie Hughes, University of Toronto

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See more of The 93rd ESA Annual Meeting (August 3 -- August 8, 2008)