Bugs and burns: Effects of fire on ponderosa pine bark beetle

Fire-damaged trees that otherwise would have survived can be killed by bark beetles (McCullough and others 1998, McHugh and others 2003). Wallin and others (2008) found that fire weakens a tree’s defense against bark beetles. An unacceptable level of tree mortality may occur after a controlled burn as a result of weakened tree defenses (Sullivan and others 2003). Breece (2006) monitored tree mortality in the Birds and Burns Network sites (coordinated by the U.S. Department of Agriculture Forest Service, Rocky Mountain Research Station) for the first three growing seasons (2004–06) after experimental implementation of prescribed fire treatments. Part 1 of this study continues to monitor these sites for an additional 3 years. In part 2, we set up additional sites in the Kaibab National Forest to monitor pre-burn bark beetle populations and stand conditions. This portion of the study provides us with data prior to the burn cycle to identify potential indicators of future high levels of bark beetle-caused mortality