Mount St. Helens, Then and Now

July 22, 1980: Mount St. Helens erupts in Washington State. (AP)

May 17, 1980: Mount St. Helens is shown in Washington state, the day before a massive eruption killed 57 people, as viewed from what came to be known as Johnston Ridge, about six miles from the volcano. (AP)

May 20, 1980: The eruption of Mount St. Helens knocked down trees along a logging road near the south fork of the Toutle River in Washington state. (AP)

Trees blown down and killed by the force of the 1980 eruption of Mount St. Helens. (Tom Hinckley)

1980: A worker at an auto dealership in Moscow, Idaho uses a blower to remove ash from the eruption of Mount St. Helens in Washington state, more than 350 miles away. (AP)

May 7, 2010: Elk graze amidst tree trunks left by the May 18, 1980 eruption of Mount St. Helens on a hillside above Coldwater Lake in Washington state. (AP)

May 7, 2010: A present day photograph of Mount St. Helens. (AP)

The green, alive trees in this picture were buried underneath snow at the time of the eruption of Mount St. Helens, allowing them to survive. (Tom Hinckley)

Fireweed, probably from a seed that blew into the site, pioneers a site near Ryan Lake in September 1980, just months after St. Helens erupted. (Roger del Moral/University of Washington)

Prairie lupine boomed in the summer of 2007, dominating the Pumice Plain that had been scoured by flows of superheated volcanic ash, debris, and gas during the eruption of Mount St. Helens in 1980. (Roger del Moral/University of Washington)

May 7: A tree stump is shown in front of Mount St. Helens, in Washington state. The volcano erupted violently 30 years ago on May 18, 1980. (AP Photo/Ted S. Warren)

May 14: Visitors walk past a tree still pointed away from the blast where it was knocked down nearly three decades earlier at what is now the Johnston Ridge Observatory at Mount St. Helens National Volcanic Monument, near Toutle, Wash. Tuesday will mark the 30th anniversary of the big eruption of May 18, 1980, that killed 57 people, knocked down a forest, filled local rivers with mudflows and rained ash far downwind. (AP Photo/Elaine Thompson)

For about 12 years after the 1980 eruption of Mount St. Helens, the deer mouse was the dominant mammal on the pumice plain. The deer mouse also survived in the blowdown zone created by the eruption. (Charlie Crisafulli)

The 1980 eruption of Mount St. Helens affected different parts of the surrounding area in different ways, through the varying remnants of the eruption. (Pacific Northwest Research Station)