Timber Harvests and Wildlife
Timber harvests provide forest products and economic return, but are also necessary to maintain healthy woodlands. No matter what type of harvest you plan for your woodland, all harvest types will have direct consequences for wildlife.
Clearcutting results in even-aged stands of shade-intolerant trees. You can achieve a mix of age classes by clearcutting adjoining stands at different times. Clearcut areas provide large amounts of edge habitat, which is beneficial to wildlife that thrive where forest edges meet nonforested areas (such as white-tailed deer). Edges tend to be abundant food sources. Clearcuts also increase stem density, thereby increasing the amount of cover for both prey and predator species. Clearcuts do not benefit wildlife species that require large and unbroken forest interiors (such as interior forest birds like the northern goshawk).
Shelterwood harvests also result in even-aged stands and allow sunlight penetration to the ground over the entire harvest area. Shelterwood harvests typically remove up to 70 percent of the trees in a stand, and then a second cut occurring 3 to 15 years later removes the remaining mature trees. Shelterwood harvests are commonly used to regenerate oak species. Acorns from red and white oaks are a staple food for many species of wildlife (such as squirrels, deer and turkeys), so shelterwood harvests often provide abundant food sources for these species.
Figure 11-3. Timber management improves forest health and wildlife habitat. Photo courtesy of Scott Craven
Timber Stand Improvement (Selective Harvests)
The most common form of timber stand improvement, or selective harvest, is thinning a stand to improve growing conditions for the remaining trees. Thinning allows more sunlight to penetrate to the forest floor. Additional sunlight will increase plant growth of wildlife cover and forage. Thinning also can open up the understory, allowing easier movement for wildlife.