North America’s Forests: Page 9 Endangered Species Handbook

Forest

North America’s Forests: Page 9

These centuries-old trees, often covered in epiphytes, plants that get nutrients from moisture and air, and lichens, including one species that drapes over branches in delicate, lacy strands, exude a lushness reminiscent of tropical rainforests. More than 140 inches of rain per year produce luxuriant tree growth and a verdant understory of ferns and hardwoods. Bright green mosses and masses of ferns carpet the ground, and a great variety of mushrooms and lichens flourish in the damp environment. In the spring, the forest floor is carpeted with beautiful white trilliums and other flowers that contrast with the deep greens of the forest. Mist and fog enshroud the giant trees, which intercept the moisture from the atmosphere, supplying the trees and the entire environment with water throughout the year (Ellis and Kane 1991).^* The southern portion of these forests is dominated by Coast Redwoods, with the record tree reaching more than 365 feet in height. Its upper branches are more than 50 feet in length. They are among the most ancient as well, some over 2,000 years old (Middleton 1992). The great Redwoods of northern California gradually melt into a forest of mixed pines, fir, cedars and hemlock.

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^*Along with the fine book by D. Middleton (1992), cited frequently here, North America's Rain Forest. The Endangered Paradise, by Gerry Ellis and Karen Kane (NorthWord Press, 1991), is an excellent resource, beautifully illustrated with the trees, plants and wildlife of these forests, and shows the devastating clearcuts contrasted with living forests. Western Forests, a book in the National Audubon Society Nature Guides series illustrates most wildlife and plant species, as well as discussing forest ecosystems.

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Douglas Firs (Pseudotsuga menziesii) grow to ages of 700 to 1,000 years old in climax growth, veterans of hundreds of periodic fires; they may reach 325 feet in height (Jonas 1993). A tree 250 years old is considered young in an old-growth forest, while middle age is 400‑500 years, and old age is more than 700 years (Middleton 1992). Recent research conducted in these forests indicates that rich diversity does not develop until forests are at least 200 years old (Moffet 1997).

Ancient Red Cedars (Thuja plicata) grew in abundance in these old-growth forests and were among the first to be cut by loggers. Old specimens are very rare at present, and activists recently saved one area with many exceptionally old and massive cedars from being logged. This forest, in Upper Priest Lake, northern Idaho, has cedars 1,500 years old. The largest trees are 20 stories tall, with trunks 10 feet in diameter. The ground beneath is carpeted with ferns, including the largest population of Braun's Holly Fern in the West. Old-growth cottonwoods also grow here. Endangered Woodland Caribou (Rangifer tarandus caribou), threatened Grizzly Bears, Fishers and Wolverines, rare Cutthroat Trout, endemic salamanders, and Harlequin Ducks are resident in the forest and wetlands. This forest covers 520 acres, worth at least $9 million to the lumber company that owns it. The US Forest Service was unable to obtain federal money to purchase it in 1996, and not until October 1997 was the grove preserved through a trade of land worth $8.7 million between the owner and the Forest Service.

More than 1,000 plant and animal species depend on old-growth forests (Egan 1994a). Invertebrate animals of the soil are highly diverse: an area 1 meter by 1 meter shelters 200,000 mites of 75 species (Middleton 1992). Fallen logs may take 500 years to rot, and this decaying wood is fed upon by the most diverse fungal network in the world (Middleton 1992). The hollow logs are used as nest holes by Red‑backed Voles and other small species. The young of these voles feed on truffles that grow in the rich soil. At least 300 insect species have been described from the rotting‑log community of organisms (Middleton 1992). A host of other insect species of the forest canopy have yet to be described.

Many vertebrates depend on the old-growth forests of the Pacific Northwest for their survival, and some of these live nowhere else. The Sitka Black‑tailed Deer and Roosevelt Elk and a unique bluish strain of American Black Bear from southeastern Alaska are among these. Bats of several species--Long‑eared, Hoary and Silver‑haired--are major pollinators and insect-predators in forests of the Pacific Northwest. Roosting in the hollow trunks of ancient trees, these bats have declined in many areas because of logging. A great diversity of amphibians lives in the moist environments of these temperate rainforests. Among them are the Slender, Olympic, Pacific Giant and Del Norte Salamanders, Pacific Tree Frog and Tailed Frog.