On the backside of steep ridges
plants were protected from the direct force of the blast.
On the backside of steep ridges
plants were protected from the direct force of the blast.
Small pacific silver fir (Abies
amabilis) and mountain hemlock (Tsuga mertensiana) trees survived the
eruption bent over beneath a late spring snow pack.
When the ash-covered snow melted,
the small trees popped free and flourished in the sun-drenched
landscape.
Large trees in the Blowdown zone
were toppled. As the trees were blown over, their large root systems
pulled up soil and plants.
Ash washed off the root systems.
This allowed the surviving plants to sprout easily.
These patches of surviving plants
were extremely important. They scattered seeds and sped the recovery of
surrounding areas.
Plants and Animals, Blowdown
Plants and Animals
Mount St. Helens
To VolcanoWorld