Cascade Mountains, USA Photograph by John Morrison   Western North America: Northwestern United States Temperate Coniferous Forests   17,300 square miles (44,900 square kilometers) -- about the size of Vermont and Massachusetts combined Vulnerable

· The Circle of Life
· Special Features
· Did You Know?
· Wild Side
· Cause for Concern
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The Circle of Life

After the eruption of Mount St. Helens in 1980, some 200 square miles (520 square kilometers) of forests were devastated. What's more, streams and lakes were dammed with lava and ash, killing 11 million fish and other aquatic life. But such large-scale disturbance is just a normal part of the circle of life in the Central and Southern Cascades Forests ecoregion. Just one year after Mount St. Helens blew, the landscape was dotted with blackberries, avalanche lilies, lupines, bracken ferns, and other pioneer plants. Animals such as killdeer, ground squirrels, gophers, and even mountain bluebirds moved in quickly. Today, the same area that was once a blanket of ash is now green with life.No matter how big or small the disturbance, from volcanoes to windstorms to fires to floods, the rich biodiversity of this ecoregion is able to flourish.

Special Features

High ridges and steep-sided valleys characterize the Central and Southern Cascades Forests ecoregion. This ecoregion includes several dormant volcanoes, including Mount St. Helens and Mount Rainier. Below these towering peaks, ancient glaciers have created a network of beautiful lakes and mountain valleys.

	The Pacific Giant salamanders of this ecoregion reach lengths of up to 12 inches (30 centimeters) from nose to tail tip.

Wild Side

The forests of western hemlock, Pacific silver fir, and western red cedar that make up the Central and Southern Cascades Forests ecoregion are home to many endemic amphibians. The largest of these, the Pacific giant salamander, hides under damp mosses, downed logs, and other debris near cold streams and mountain lakes. These giant amphibians use a terrible-tasting milky solution secreted by glands on the top of their tails to help protect them against predators such as weasels, mink, mergansers, river otters, and water shrews. Under the forest canopy, northern spotted owls and northern goshawks fly. Because they have large home ranges and require old-growth forests to nest and feed, northern spotted owls are good indicators of the health of the Cascade Forests. Another good indicator species is the tailed frog, which lives in and near mountain streams that have cold, fast-flowing water. These frogs are always located in undisturbed forests, because any silt caused by logging or road building that gets in the streams can kill the eggs and tadpoles.

Cause for Concern

Extensive logging, road building, and hydroelectric development have caused serious damage to this ecoregion. Logging remains the primary threat to biodiversity, but other growing threats include fire suppression, exotic species invasions, and road building. A century of fire suppression has caused changes in communities of plants that depend on periodic fires for their stability. Human attempts to stop these fires altogether have caused a buildup of natural fuels and thus have inadvertently increased the extent and severity of fires when they do happen. The absence of periodic fires has also resulted in declines in rangeland integrity and increases in exotic species invasions.

For more information on this ecoregion, go to the World Wildlife Fund Scientific Report.