In praise of dead trees

Dead. Most of us have negative associations with the word. After all how did Death Valley get its name? Not because it was a favorite vacation spot for prospectors. Is anyone interested in fishing the Dead Sea? And when we say someone looks like “death warmed over” it’s not usually taken as a compliment. So it’s not surprising that most of us tend to view dead things as undesirable, unless we are talking about mosquitoes and rattlesnakes. (Actually I appreciate both and don’t advocate early death for either.)

We carry this cultural bias to our view of forests. Like most people I once viewed dead trees as an indicator of some presumed problem in the forest – that a ‘healthy” forest was one with a minimum of dead trees and largely free of wildfire, insects, and disease. Oh yes, I knew that a few snags were good for woodpeckers, and as a fly fisherman I understood that trout tended to be found hiding behind logs in the stream. I suffered from the same cultural bias as most people and thought that large numbers of dead trees meant that the forest was “out of balance” or “sick.” But the more I studied ecology, the more I questioned these assumptions. I now understand that large numbers of dead trees are critical to functioning forest ecosystems and sometimes, at the risk of hyperbole, I occasionally say they are ultimately more important to forest ecosystems than live trees.

There is no disputing the ecological importance of dead trees. Dead trees and down wood play an important role in ecosystems by providing wildlife habitat, cycling nutrients, aiding plant regeneration, decreasing erosion, and influencing drainage and soil moisture and carbon storage, among other values.

Richard Hutto, an ecology professor at the University of Montana, sums up this new way of thinking about the long-term ecological value of dead trees when he notes, “Snags are important biological legacies that are passed from one forest generation to the next.”

Old perceptions about dead trees are rampant in our society. In a January 2009 Christian Science Monitor article about bark beetle and forests, Tim Love, Seeley Lake District Ranger on the Lolo National Forest, was quoted saying there was an “overabundance” of dead trees on his district from both wildfire and beetles. His viewpoint is all too common.

In our traditional paradigm, fires and insects are generally viewed as undesirable, and tolerated only if they are small, limited, and controllable. We spend billions annually trying to contain wildfire and insect outbreaks based upon the presumption that these natural processes are “destroying” the forest. Even though there is now some grudging acceptance of some limited wildfires and even some small insect attacks as potentially “beneficial,” most people still view large stand replacement fires and large beetle outbreaks as “unnatural,” “abnormal,” and something to suppress, slow, and control.

A new perspective is slowly taking root that questions the idea that an abundance of dead trees are bad and whether we are “losing” anything to wildfire and insects. Indeed, large stand replacement blazes and major insect outbreaks may be the ecological analogue to the forest ecosystem as the hundred year flood is to a river. Such natural events are critical to shaping ecosystem function and processes.

This article has been excerpted from: ‘In praise of dead trees’. Courtesy: Counterpunch.org.