The session, which has been organized by Edward Johnson from the University of Calgary and Jon Keeley from the US Geological Survey, will examine the different ways fire moves through various ecosystems types. It has been well established, say Johnson and Keeley, that ecosystems dominated by ponderosa pine have a long history of frequent surface fires and infrequent crown fires. The successful suppression of surface fires by humans during the last century has led to a large accumulation of fuel, which has in turn led to an increase in damaging and uncontrollable fires in the crown areas of trees. In order to manage fire risk, land managers have adopted a method of planned or "prescribed" burns, whereby fires are purposefully set in areas where fire has not recently occurred. Ecologists refer to this as the "ponderosa pine model." While there is evidence that this model may be applicable to some open canopy forests, some scientists question the logic of applying it to all ecosystems. Several speakers at this symposium will present evidence regarding the ineffectiveness of using this model on other systems.
Keeley, Paul Zedler from the
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Contact: Nadine Lymn
nadine@esa.org
202-833-8773
Ecological Society of America
5-Aug-2001