A couple of weeks ago, Sierra and I were in Ketchum, Idaho taking a much needed mid-October vacation. The weather was great, and the fall color was incredible, so heading out on multiple hikes was a no-brainer. On our hikes, I found myself increasingly drawn to all of the snags. Forested areas like those found in the Sawtooth National Forest are bound to have a significant amount of standing dead trees. After all, trees don’t live forever; just like any other living being, they die – some of old age, some of disease or lightning strike or any number of other reasons. But death for a tree does not spell the end of its life giving powers. In the case of snags, it’s really just the beginning.
Death might come quick for a tree, but its rate of decomposition is slow. Fungi move in to begin the process and are joined by myriad insects, mosses, lichens, and bacteria. The insects provide food for birds, like woodpeckers and sapsuckers who hammer out holes in the standing trunk. As primary cavity nesters, they also nest in some of these holes. Secondary cavity nesters make a home in these holes as well. This includes a whole suite of birds, mammals, amphibians, and reptiles. Without the habitat provided by snags, many of these animals would disappear from the forest.
Eventually snags fall, and as the rotting continues, so does the dead tree’s contribution to new life. It’s at this point that snags become nurse logs or nurse stumps, providing habitat and nutrients for all sorts of plants, fungi, and other organisms.
Unfortunately I can’t bring a you a complete representation of the many snags of Sawtooth National Forest. You’ll have to visit sometime to see them all for yourself. Instead, what follows is a small sampling of a few of the snags we saw near Ketchum and Stanley.
For more snag and nurse log fun, check out the following episodes of Boise Biophilia: