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Forest is the native vegetation of almost half of mainland Canada and the United States. Before European settlement, forestlands dominated the eastern, and much of the northern, part of the continent. Grasses covered a large part of the continental interior. Desert vegetation is native in the Southwest, tundra in the far north. Over much of the continent, however, human activity has virtually eliminated native vegetation.
Coniferous Forests of the West
Along the Pacific coast from Alaska to Northern California, evergreen coniferous forest grows luxuriantly, watered by moisture-laden winds blowing from the ocean. This lowland forest includes some of the largest and longest-lived trees in the world. North of California, characteristic trees include Sitka spruce, western hemlock, and western red cedar. Douglas fir, one of the major timber species in North America, is also common. The northwest coastal coniferous forest is sometimes called temperate rain forest because, in its lushness, it resembles the tropical rain forests. Many of the trees of the coastal forest have been cut for timber.
In California, the dominant coastal conifer species is the coast redwood. The tallest tree in the world, coast redwood reaches 330 feet (100 meters) and can live two thousand years. Coniferous forest also grows along the Cascade Mountains and the Sierra Nevada. Trees of the Cascades include mountain hemlock and subalpine fir at high elevations and western hemlock, western red cedar, and firs somewhat lower. Sierra Nevada forests include pines, mountain hemlock, and red fir at high elevations; and red and white firs, pines, and Douglas fir somewhat lower. Ponderosa pine is dominant at low mountain elevations in both of these Pacific ranges.
The giant sequoia, long thought to be the largest living organism on earth, grows in scattered groves in the Sierra Nevada. (The largest organism actually may be a very old tree root-rot fungus that covers 1,500 acres in Washington State.) Although shorter than the coast redwood, the giant sequoia is larger in trunk diameter and bulk. It can reach 260 feet (80 meters) tall and 30 feet (10 meters) in circumference.
Coniferous forest also dominates the Rocky Mountains and some mountainous areas of Mexico. In the Rockies, Engelmann spruce and subalpine fir grow at high elevations, and Douglas fir, lodge pole pine, and white fir somewhat lower. Ponderosa pine grows throughout the Rockies at low elevations and is a dominant tree in western North America.
Boreal Coniferous Forest
Just south of the Arctic tundra in North America is a broad belt of boreal, coniferous, evergreen forest.
Continue of the article: Boreal Coniferous Forest
Eastern Deciduous Forest
A forest of mainly broad-leaved, deciduous trees is the native vegetation of much of eastern North America.
Continue of the article: Eastern Deciduous Forest
Other Forests
The southeastern United States, excluding the peninsula of Florida, once supported open stands of pine and also mixed evergreen and deciduous forest.
Continue of the article: Other Forests
Central Grasslands
The central plains of North America, a wide swath from the Texas coast north to Saskatchewan, Canada, were once vast grassland, the prairie.
Continue of the article: Central Grasslands
Scrub and Desert
In the semiarid and arid West, the natural vegetation is grass and shrubs.
Continue of the article: Scrub and Desert
Tundra
Tundra vegetation grows to the northern limits of plant growth, above the Arctic Circle, in Canada
Continue of the article: Tundra
Coastal Vegetation
Along the coasts of the Atlantic Ocean and the Gulf of Mexico, the soil is saturated with water and is very salty.
Continue of the article: Coastal Vegetation
See also: North American Agriculture
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