According to the organizers of the symposium, Matt Brooks (United States Geological Survey) and Mike Pellant (US Bureau of Land Management), studies "have emphasized the widespread need for fire reintroduction as an important ecosystem process, but the potential effects of fire restoration on plant invasions...have not been addressed." Concern about invasive species has existed for years. Scientists have expressed concern over invasive plants' threat to biodiversity, and certain types have been shown to increase fire risks. Researchers at the session will describe the relationship between fire and invasive plants and explore promising new lines of research.
Fires may prove an effective tool against certain invasive plants, but studies are showing some species may have the competitive edge. Jon Keeley (US Geological Survey) will review the conditions that hinder and promote alien plant populations in his presentation, "Impact of fire management practices on invasive plants." Looking at species within conifer forests of the Sierra Nevada in California, Keeley has found evidence suggesting fire severity "may have substantial impacts on the invasion process." According to Keeley, fuel breaks and controlled burns could promote the growth of invasive alien plant species, clogging out the native inhabitants as new land is cleared by fire.
In "Impacts of invasive alien plants on fire regimes" David Richardson, Philip Rundel, and Brian Van Wilgen (Institute for Plant Conservation, University of Cape Town, South Africa), will describe the possible impacts of invasive grasses, trees and shrubs on several ecosystems from around the globe. Invasive plants "have the potential to alter the fire regime in many ways," according to the researchers. Reviewing studies from Hawaii, South Africa, and North America, they will discuss how changes in the types of plants living in an environment alter the pattern and severity of fires.
Once the fires have been eliminated, resource managers must find a way to restore land without increasing the number or variety of invasive species. Describing the restoration of ecosystems after wildfires, Mike Pellant (US Bureau of Land Management) and David Pyke (US Geological Survey) will illustrate the effectiveness of planting native species such as Bluebunch wheatgrass (Pseudoroegneria spicata) and Big sagebrush (Artemisia tridentata) to limit the spread of such invasive plants as Cheatgrass (Bromus tectorum). Their discussion, "Can post-fire restoration minimize the dominance of invasive species?" will address alternative strategies to further establish soils and reduce the presence of invasive weeds in the environment.
Other speakers will continue the symposium's theme by analyzing the relationship between fire and invasive species in more detail. Joseph DiTomaso (University of California, Davis) will discuss the integration of fire with other control methods to manage invasive species. James Grace (US Geological Survey), Richard Hobbs (Murdoch University, Australia) and colleagues Matthew Brooks (US Geological Survey) and Carla D'Antonio (US Department of Agriculture) will each offer their findings on the ecology and management of fire and invasive plants.
For more information about this session, and all ESA Annual Meeting Activities, visit the ESA website: http://www.
The symposium, "Fire and Invasive Plant Ecology and Management: The Need for Integration to Effectively Restore Ecosystems," will occur 6 August 2002 at the Tucson Convention Center.
The Ecological Society of America (ESA) is a scientific, non-profit, 7,800-member organization founded in 1915. Through ESA reports, journals, membership research, and expert testimony to Congress, ESA seeks to promote the responsible application of ecological data and principles to the solution of environmental problems. ESA publishes three scientific, peer-reviewed journals: Ecology, Ecological Applications, and Ecological Monographs. Information about the Society and its activities is published in the Society's quarterly newsletter, ESA NewSource, and in the quarterly Bulletin. More information can be found on the ESA website: http://www.