Lassen Volcanic, California on the map. National Park Lassen Volcanic (California state) on the map of US

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Lassen Volcanic, California on the map. National Park Lassen Volcanic   (California state) on the map of US

Right: The Devastated Area, with Lassen Peak looming in the background. Lassen Peak began as a volcanic vent on Mount Tehama's northern flank.

Below: Bumpass Hell, the largest geothermal area in the park, features fumaroles, boiling mud pots and waters above 212 degrees Fahrenheit. The man who named Bumpass Hell lost a leg as a result of falling into the boiling waters.

Lassen Volcanic, California

Established: 1916   Acreage: 106,372

Lassen Peak lies along the Ring of Fire, a chain of volcanoes—active, dormant and extinct—that circle the Pacific Ocean. This zone marks the edges of plates that compose the earth's crust. The movement of these plates creates volcanoes and earthquakes. As the expanding oceanic crust is thrust beneath the continental plate margins, it penetrates deep enough into the earth to be remelted. Pockets of molten rock result (magma), which become the feeding chambers for volcanoes.

About 500,000 years ago, Mount Tehama, a great Pacific Ring of Fire stratovolcano, gradually built up through countless eruptions. Lassen Peak began as a volcanic vent on Tehama's northern flank. It is considered the world's largest plug dome volcano, rising 2000 feet (610 meters) to attain the height of 10,457 feet (3200 meters) above sea level.

In May 1914, Lassen Peak erupted, beginning a seven-year

cycle of sporadic volcanic outbursts. The climax of this cycle occurred in 1915, when red lava spilled through a notch in the crater rim and flowed down the western slope a quarter of a mile, then hardened. On the northeast side the hot lava melted the deep snowfield, causing a huge river of mud to flow rapidly down the mountainside, carrying boulders the size of of an ordinary bedroom. Three days after that Lassen spewed an enormous mushroom cloud toward the sky. Meanwhile, on the northeast side another blast struck, widening the path of destruction to more than a mile, and continuing for five miles down the mountain, mowing down trees and all signs of life in its path. All of this activity generated nationwide attention, and brought about Lassen's establishemnt as a national park.

The Devastated Area and the Chaos Jumbles Area of the park demonstrate how landscapes recover from volcanic activity. Both are important post-volcanism plant succession sites that are recovering directly to conifers without preparation by herbaceous plants. Many disturbed areas throughout the park are reforested with young forests much more varied than the original forests. The reason for this appears to be the lack of competition during the early stages of growth. Eventually, only a portion of the trees now present will take control of the area. The park's plant life is a mix of species from the Sierra Nevada and the Cascades, which results in an abundance of species. Lassen boasts 715 plant species, while nearby Mount Shasta has only 485.

The Lassen area was a meeting point for four Indian groups who camped here on a seasonal basis. In 1911 a Yahi Indian named Ishi appeared in Oroville. Ishi's appearance was quite a surprise because his tribe was thought to be nonexistent. He lived out his days at the University of California Museum, where he was an invaluable ethnological resource. Ishi was considered the last Stone Age survivor in the United States.

California's gold rush in 1848 brought the first white settlers. Two pioneer trails, developed by William Nobles and Peter Lassen, are associated with the park. In 1851 Nobles discovered an alternate route to the state, passing through Lassen. Sections of the Nobles Emigrant Trail are still visible in the park.

Lassen Volcanic, California on the map. National Park Lassen Volcanic   (California state) on the map of US