Discussions regarding the ecological value of wilderness compared to an actively managed forest often centers around the health and well being of specific members of the wildlife community. While the flora and fauna that a tract of wilderness supports may be strikingly similar to that which occurs in periodically logged woodlands, the relative abundance of the various plants and animals contained in each is often quite different. In wilderness regions, there eventually develops a much higher concentration of those organisms whose lives are connected either directly or indirectly to the presence of dead wood.
Forests that are protected from timber harvesting operations contain substantially more dead wood on the ground and on the stump. While some trees that succumb to a disease or insect infestation may remain upright for only a few years after they die, many remain standing for decades before they eventually fall. Standing dead trees, especially ones that are larger than a foot in diameter, harbor numerous living entities and provide many animals with shelter.
Forest dwelling invertebrates are particularly attracted to dead timber as their bark is often loosely connected to the trunk which allows space for placing eggs, or permitting nymphs, larvae and adults to reside there during the winter months. Pulling a partially rotted section of bark from a dead tree in summer typically reveals dozens of critters ranging in size from pin-head spiders to inch long centipedes. The grubs of wood boring beetles, along with small colonies of carpenter ants, are frequently encountered when chopping out a chunk of wood from a trunk that has just started to decay. Larger creatures, like woodpeckers, chickadees, nuthatches and the brown creeper occasionally scour such standing wooden columns for the invertebrate matter which they harbor.
Many birds also rely on the cavities that develop in such dead trees for roosting sites during winter and nesting locations in spring and early summer. Birds as large as the wood duck, merganser, and screech owl have a much easier time locating a nesting cavity in a parcel of wilderness than in an area in which trees have been removed for firewood or lumber.
Mice and flying squirrels also rely heavily on cavities in dead trees for their nests. Even though these creatures cease breeding and no longer have young in their care during the latter part of autumn and throughout the winter, they still maintain a nest in which they take shelter when they want to rest when the weather is cold.
Large rotting logs on the ground create a haven for many small organisms, as such massive objects form a favorable microhabitat that is most attractive to those members of the wildlife community that are all too often overlooked. As wood rots, it develops a sponge-like quality that better enables it to retain moisture. This allows the soil beneath a large dead log to remain moist during prolonged periods of dry weather, which lures moisture-sensitive animals like salamanders, wood frogs and toads to these spots. As cold weather sets in during late autumn, the soil fails to freeze as quickly beneath such massive objects, and when it eventually does, the frost line never goes down as deep below a log carpeted with moss as it does on a section of soil that has been temporarily cleared of trees.
Unquestionably, there are numerous species of wildlife that do much better in a forest that is periodically thinned. There is no denying that the white-tailed deer thrives in woodlands in which timber is routinely harvested. This is why big game sportsmen prefer to hunt in places where logging has taken place. Creatures that depend on deer, like the coyote also tend to have higher populations in areas that have been worked by foresters and lumberjacks.
A tract of land that is cared for by a responsible timber company can have a clean and orderly appearance. This stands in sharp contrast to the unkempt look of a wilderness forest which is littered with rotting logs, fallen limbs, diseased trees, and patches of dense underbrush creating impassable obstacles in many scattered spots. Yet appearances are often deceiving, as the wilderness woodland typically has a more diverse and vibrant ecology. From mushrooms to salamanders to woodpeckers, a wilderness woodland is able to support a greater abundance of life than a managed forest.
I fully realize that economic issues come into play when discussing the value of wilderness, however, I know far less about economics than I know about ecology.
A version of this story was first published on the Adirondack Almanack in August, 2012.