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NATURE · HISTORICAL MARKER
The Pumice Plain
Cougar, Washington
· Tenacious Pioneers Regrow a Forest
Nature
2
On May 18, 1980, the lush ecosystem on the north side of Mount St. Helens was buried beneath a massive landslide and repeatedly covered with searing avalanches of hot gases and nutrient-poor pumice and ash. Plant and animal pioneers are transforming this initially barren landscape, and thanks to these changes, trees are now beginning to grow. Ferns, mosses, and other understory plants will sprout in the eventual shade, and a new forest has begun.
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Cougar, Washington
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