“Snag” is the traditional forestry word for a standing dead, or partially dead, tree. Several years ago, biologists adopted
a more descriptive and deserving term: “wildlife tree”.
With the exception of living plants, probably no other single component of the woodland environment supports more
animal life. In North America, about 85 species of birds, at least 50 mammal species, and roughly a dozen reptiles and
amphibians rely on snags for shelter, food, mating, resting, nesting and other critical functions. In addition, dozens of
invertebrates — millipedes, beetles, spiders, worms, ants and more — also call snags “home” (or at least “snack bar”). In
all, says the U.S. Forest Service, some 1,200 forms of fauna rely on dead, dying or rotted-hollow trees.
But by far the greatest benefit of snags is the cavities — holes used for nests and shelter — that they foster. For many
birds and animals, no better home exists than a hole in wood. Woodpeckers, chickadees, bluebirds, nuthatches, owls,
wrens, tree swallows, raccoons, squirrels, bats, opossums, flying squirrels, porcupines — these are only a few of the
species that require or prefer cavities.