Washington’s state tree, the western hemlock, is widely used in the forest industry as a pulpwood species, and it and Douglas fir are two of the most abundant low-elevation trees in the state. Above 3,000 feet in elevation, Pacific silver fir and mountain hemlock take over. Bigleaf maples are distinguished by—you got it—their enormous leaves, up to a foot across. The Pacific madrona is found along the coast and characterized by waxy, evergreen leaves and peeling reddish bark that exposes a smooth underskin. Other common trees are the western red cedar, Sitka spruce, grand fir, black cottonwood, red alder, and vine maple. Northeast Washington and parts of the Cascades have other species, including lodgepole pine, western larch, western white pine, ponderosa pine, and Engelmann spruce.
Olympic Rain Forest
At Olympic National Park, the Hoh, Queets, and Quinault River Valleys constitute the better part of the Olympic rain forest, an area unique in the world. The largest known western hemlock and Sitka spruce grow in the Quinault Valley, the largest Douglas fir is in Queets, and the largest red alder is in the Hoh. The four major species here—the Sitka spruce, western red cedar, Douglas fir, and western hemlock—all grow very tall: trees average 200 feet, with many topping 300 feet.
The height of the trees isn’t the only fascinating aspect of the rain forest: The visitor is immediately struck by how green everything is, and how pristine. These areas have never been logged; what you see is nature, pure and simple. Enormous trees spring out of the long-since-decayed “nursery logs” that gave them life, with club moss eerily draping the branches; ferns and mosses cover nearly every inch of available ground in a thick carpet. Though most rainfall occurs from fall to spring, even summer days feel damp from high humidity and ocean fog. And it isn’t just trees that one finds in these rainforests, but an incredible diversity of ferns, mosses, shrubs, herbs, and other plants, along with many kinds of birds, mammals, insects, and amphibians.
Old-growth forests are defined as being at least 250 years old, though some stands are actually far older, approaching 1,000 years. Because of the tall overstory trees that moderate temperatures and hold much of the snow, original forests are more stable than cutover areas and less susceptible to climatic extremes. This helps the survival of forest animals by allowing them to browse at all times of the year. It also allows for a multilayered understory of trees, bushes, and herbs that can support a larger variety of animal life. In addition, defects in the old trees and standing dead trees—called snags—provide nesting sites for birds, flying squirrels, and other animals, while the fallen trees create nutrient-rich mulch as they decay. In many old-growth forests, these fallen giants become “nursery logs,” with new trees sprouting in a straight line along the trunk.
© Ericka Chickowski from Moon Washington, 8th edition