Department of Biological Sciences, Fort Hays State University Instructor: Mark Eberle                  Course Homepage

Cascade Volcanoes Mount St. Helens NVM Washington Lassen Volcanic NP California

Prior to its most recent eruption, the conical shape of Mount Saint Helens did not bear the marks of glaciers, which indicated that it was active more recently than other Cascade volcanoes, such as Mount Rainier. Mount Saint Helens erupted violently in May 1980, when a landslide on the north flank allowed the pent-up pressure of steam in the magma rising within the volcano to escape. The montane forest and riparian communities destroyed in the surrounding blast zone are slowly beginning to recover. Trees in these forests live for centuries, so the more than 25 years that have elapsed since the eruption represent a relatively short amount of time in the life of a forest community. Those of us with lifespans measured in decades tend to be a little impatient with nature. The low vegetation now growing in the blast zone benefits wildlife, such as the 2 groups of elk that we saw grazing in July 2000 in the valley situated between us and the volcano in the photograph below on the left.