Thirty-six years ago on Wednesday, Mount St. Helens in southern Washington state erupted, killing 56 people and laying waste to more than 200 square miles of surrounding forest. Residents of the cities and towns near the volcano remember the sky turning black and ash raining down from the clouds. For years following the volcanic blast, the area around the mountain resembled a moonscape of dead trees and barren land. Today, life has begun to take root again, offering scientists a rare chance to see how nature reassembles itself after upheaval. John Bishop, an evolutionary biologist at Washington State University-Vancouver, leads a team of researchers who hike out to the mountain to study the species that are recolonizing its desolate slopes. The first plant to return was alpine lupine, which paved the way for woody plants like the Sitka willow to take root. Although these plants form the starter kit for forest growth, an invasive species of weevils prevents the willow from growing large enough to provide sufficient habitat for more species of animals. Even though the Mount St. Helen’s ecosystem has come a long way from where it was 36 years ago, it still has a long way to go. “We’re centuries away from replacing the old-growth forest that was there,” Bishop said.

ecology — a branch of science that deals with the relationships between groups of living things and their environments vegetation — plants that cover a particular area weevil — a small insect that eats grains and seeds and that may ruin crops