Slope Recovery Difference on Mount St. Helens

January 06, 2009


Photographer: Linda Weirather
Summary Author: Linda Weirather

These two photos show the dramatic difference, just a few meters apart, between the south-facing (top picture) and north-facing (bottom) slopes of Johnston Ridge, the tourist destination with spectacular views of Mount St. Helens volcano. Mount St. Helens summit is actually 10 miles (6.5 km) to the right of these photos. The south slope faces the volcano. The debris avalanche that occurred during the 1980 eruption spilled over the top of this slope in many places. As the avalanche slid back down 1,150 ft. (350 m) to the valley floor, the mountainside was scraped to bedrock. Today, it presents a precipitous and eroded cliff below the trail. The north side of the ridge is a softer landscape where snow and water can collect, favorable for re-growth of fir and alder. Forests here were entirely seared by the volcanic blast. Scattered firs are now 6 – 14 ft (2 – 4 m) tall. Photo taken on July 9, 2008.