Habitat - These forests, which include mixtures of different kinds of deciduous, coniferous, or deciduous/coniferous trees occur mainly on glaciated land which has deep, rich layers of soil. Usually two or more kinds of deciduous trees dominate the area. These might include associations of beech-sugar maple or sugar maple-basswood typical in the East or black cottonwood-red alder and birch-poplar-cottonwood in the West.
These forest are the most diverse in animal life because they provide the greatest range of food, cover, and protection. For example, trembling aspen, which is the most widespread tree in North America, when interspersed in coniferous trees, provides homes for such animals as deer, grouse, bear, snowshoe hare, and beaver. Some northern forests contain mixtures of pine, hemlock, and an assortment of hardwoods.
Although evergreen provide cover and food for some birds year-round, most species found in this habitat are summer visitors. The Western Tanager, Rose-breasted Grosbeak, Ruby-crowned Kinglet, and Northern Oriole are a few of the summer songsters.
