Tree ring dating of prehistoric eruptions of Mount St. Helens

This study includes two topics: 1. Dating of prehistoric eruptions of Mount St. Helens using tree ring patterns of living trees and of dead, buried trees. Using increment cores of Douglas fir (Pseudotsuga menziesii), three prehistoric eruptions were dated at 1480, 1482, and 1800 A.D.   View the full abstract (69A)