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13 Chapter One: Forests of North America

Mixed Forests Not all forests are made completely of either deciduous or coniferous trees. “Mixed forests,” with some of both types of trees, are especially common in the eastern regions of the United States and Canada, as well as around the Great Lakes. These forests include trees such as oaks, beeches, maples, and birches, as well as pines, firs, and spruces.

The forest in Denali National Park, Alaska, contains both coniferous trees, such as pines, and deciduous trees, such as birches.

Conifers grow best where there are short summers and long winters. This is the case in the northern sections of North America and other continents. Some of these areas may have heavy snow for about half of the year. These trees are perfectly adapted for their cold, snowy environment. The needles on the trees often have a coating that feels somewhat waxy; this helps prevent the loss of water. The branches are long and bend easily, which allows them to ride out the heavy snow that falls. The floor of a conifer forest is different from that of other forests. When the needles of these trees die, they fall to the ground and pile up. The ground takes on a soft, almost spongy feel underfoot. The needles are rather acidic, which makes the soils of conifer forests less fertile than others. Conifer trees can grow to great heights and often block