Managing Aspen (popple) Forests for Ruffed Grouse
Through the eyes of a ruffed grouse, an aspen forest is an incredibly valuable asset. First, the dense, young growth of a recently harvested aspen stand provides a grouse protection from predators, especially hawks and owls. Also, the flower buds, found on mature male aspen trees, are a life-saving food for ruffed grouse during winter and early spring when snow cuts off ground feeding. Because grouse rely on both young and mature aspen, ideal ruffed grouse habitat consists of small 5- to 20-acre aspen patches all close together but of different ages.
In addition to the importance of aspen forests to ruffed grouse, they are important to many other species of wildlife as well. White-tailed deer rely upon aspen throughout much of the year for both food and cover. American woodcock use young aspen stands, particularly those on relatively moist sites. Moisture in the soil keeps earthworms, the principal food for woodcock, available near the earth's surface.
Many songbirds, including the golden-winged warbler, chestnut-sided warbler and field sparrow, are more abundant in young aspen stands than in other forest habitats. But their numbers are declining throughout eastern North America, along with those of ruffed grouse and woodcock, as our aspen forests mature and leave a scarcity of young, dense forests.
Private landowners interested in promoting ruffed grouse on their properties should manage their forests to sustain existing stands of aspen. Aspen trees reproduce by root suckers. The root system of a single mature aspen may support hundreds of buds, each with the potential of sprouting and developing into a young tree when its "parent," the mature tree, is cut. Because these young sprouts require full sunlight, all of the trees within an existing stand of aspen must be cut at the same time (a harvesting method known as clearcutting) to allow the young trees to develop. Clearcutting is used because the shade from even a few trees left standing can hinder aspen growth and negatively affects ruffed grouse habitat quality.
Ruffed grouse are most common in aspen stands that are approximately 10 years old. At this age, the young aspen trees are about the diameter of a half-dollar coin. The ideal ruffed grouse habitat, however, lasts for only seven to eight years. By the time they're 15 or 20 years old, many aspen trees have died and fallen to the ground. This natural thinning allows the remaining trees to take full advantage of available sunlight and soil nutrients. But as the stands thin themselves, they become more open and provide grouse with less protection from predators.
Therefore, landowners who are interested in ruffed grouse should try to maintain aspen stands of different ages, if possible. This will ensure that as one aspen stand becomes too old for grouse, a nearby stand of a younger age is just becoming ideal ruffed grouse habitat. To create such diversity, the landowner may "break up" a mature stand of aspen by harvesting one portion now and another in five to 10 years. If, however, due to advanced age and declining health, the mature aspen is unlikely to survive another five to ten years, the entire stand should be regenerated through a single clearcut harvest. If ruffed grouse are a management objective, it is far better to regenerate the entire stand of aspen through cutting than to allow the uncut portions of the stand to become dominated by maple or some other species of less benefit to grouse.
In summary, aspen (popple) forests are home to many types of forest wildlife and are critically important to ruffed grouse. Landowners interested in ruffed grouse, white-tailed deer and a long list of wildlife species that share cover with grouse and deer, should do everything they possibly can to sustain their aspen forests through active forest management.