Thinning Plan Needs Review
Thinning and not burning slash would endanger homes more, rather than less
Smoke rose ominously over Santa Fe's watershed Monday, prompting dozens of calls to the Forest Service to report the problem. In fact the fires were planned and, at least according to a number of recently completed studies, were necessary once the city and the Forest Service embarked on the thinning program several years ago.
The studies, involving Western forests, show that wildfires across thinned areas of forest burn hotter and kill more trees than wildfires in unthinned forest- unless the thinned areas have been intentionally burned after thinning to consume slash and other debris.
We supported the decision to thin the watershed- it seemed like common sense to reduce the possibility of catastrophic wildfire in the area surrounding the source of roughly half the city's drinking water. Not everyone agreed- WildEarth Guardians and other environmental groups fought the decision. Their objections were various, including that thinning would involve machinery and human activity that ultimately might do as much damage to the watershed as a wildfire would. Incidentally, another, decade-old study suggested that thinning is effective only if it is continuous- an expensive proposition.
As drought and climate change increase fire danger in the West, these experiments here and elsewhere will contribute to our understanding of the best practices in this area.
In the meantime, having thinned, we now must burn: According to the recent studies, leaving the watershed alone would have been a better course of action than thinning but not burning the slash. Tree mortality- the number of trees killed by wildfire- is greatest where thinned forests have remained unburned.
These studies raise an interesting question about the wisdom of the city's newest thinning plans, involving several hundred acres around the popular Dale Ball Trails system in the foothills. These trails wind around and alongside settled areas- meaning burning the thinned areas to get rid of slash and debris may be hard to do, not to mention unpopular with nearby homeowners. But, per the studies, thinning and not burning would endanger these same homes more, rather than less.
A month or so ago, city councilors sent this thinning proposal back to the drawing board, saying it needed more study. In this case, that may have been the right move.
Copyright 2006 Albuquerque Journal - Reprinted with permission