Cleacutting is the practice of removing all trees of whatever size from a swath of land, leaving a field of crushed vegetation, bare stumps and mud. It is the preferred tactic of the forest industry because it is cheap and easy to do on a large scale; but it is by ecological standards a very bad form of logging.
Clearcutting requires extensive systems of forest roads and skid trails, where the forest soil is bulldozed and laid bare. The heavy logging equipment compacts the soil, and the disturbance of the soil results in erosion, which contaminates streams with silt and nutrients.
Widespread clearcutting produces a generalized deterioration of the land: more logging roads and machinery in the forest, fmore human intrusions, more trash, more erosion, invasions of nonnative organisms, damaged soils, and diminishment of many native plant and animal species—in addition to the loss of the trees themselves.
Though promoted as a form of agriculture, with trees as its harvestable crops, clearcutting violates agriculture’s primary rule: give back what you take. All experienced farmers and gardeners know that if you do not return to the soil at least as much organic material and nutrients as you take in harvest, the soil loses fertility with each succeeding crop. But industrial forestry gathers its so-called "harvest" without giving back—except (rarely) for a little petrochemical fertilizer. The trees, which in nature would die, rot, and replenish the soil, are trucked away, and with them go the nutrients they have absorbed.
If the system is left undisturbed long enough, of course, eventually the lost biomass and nutrients are restored. But this does not mean that clearcutting does no damage. An undisturbed forest not only maintains itself, but actively builds soil, enriching the foundation from which all land-based life springs. If succeeding "harvests" occur as soon as the nutrients and biomass return to pre-cut levels, this enrichment is halted and the system no longer grows richer. If they occur earlier, it is reversed and the system becomes poorer. In any case, removing the trees always makes the forest system and forest land poorer in nutrients and biomass than if it had been left alone.
When we look at specific effects on plants and animals the damage of clearcutting becomes more evident still. Fragmentation of forest habitat is especially damaging to song birds, sixty percent of which are today in population decline. Clearcutting dries out soil and crushes the burrows of salmanders, killing over seventy-five percent of the salamanders in mature forest stands. Recent studies suggest that the number of species of understory plants is significantly reduced after a clearcut and takes several centuries to recover—and rare is the forest that, once clearcut, is left to grow again for several centuries.
The forest industry argues that clearcutting is better than the alternative of high-grading: cutting only the large, healthy, commercially valuable trees, leaving those that are less healthy and less marketable. It is undeniable that high-grading, has seriously damaged the forests of East Tennessee. Since high-grading tends to eliminate the fittest trees, leaving the weakest and most disease-prone, high-graded forests are dominated by species of little commercial worth and by damaged or unhealthy trees. The forest industry refers to such forests as "low grade." This judgment, however, reflects the commercial value of the trees, not their ecological value. Trees that are classified as low grade commercially may still serve important ecological functions, such as shading and enriching the soil, filtering and freshening the air, improving water quality, preventing erosion, and providing habitat for understory plants and for many species of animals. They also have an important economic value: providing the grand, green vistas that attract tourists—and for some they satisfy the sense of beauty or deeper longings of the spirit. It is doubtful that any such values can be enhanced by clearcutting.