The eruptive output volume totaled , dwarfed by the 1980 eruption of Mount St. Helens , which had a volume of . The region on the volcano 's northeastern flank destroyed by the eruptions , in area , is now known as the Devastated Area , and it along with other deposits from the volcano has been altered by erosion and regrowth of vegetation , though the vegetation in Devastated Area is sparse due to its siliceous ( rich in silica ) , nutrient-deprived soil , which can not sustain normal tree growth due to its lack of water retention . Due to their small size and thin deposits , the 1915 eruptions will likely not be well-preserved geologically
1980 eruption of Mount St. Helens
1980 eruption of Mount St. Helens
Lassen Peak