Gifford Pinchot National Forest in Skamania County, Washington — The American West (Northwest)

The Pumice Plain

Tenacious Pioneers Regrow a Forest

— Mount St. Helens National Volcanic Monument —

The Pumice Plain Marker image. Click for full size.

Photographed By Cosmos Mariner, July 17, 2015

1. The Pumice Plain Marker

Inscription. You are looking at a past and future old-growth forest. On May 18, 1980, the lush ecosystem flanking the north side of Mount St. Helens was buried beneath a massive landslide, and covered repeatedly with searing avalanches of hot gases and nutrient-poor pumice and ash.

Tenacious plant and animal pioneers are transforming this initially barren landscape. Thanks to these changes, trees are now beginning to grow. Ferns, mosses and other understory plants will sprout in the eventual shade. A new forest has begun.

Erected by Gifford Pinchot National Forest, US Department of Agriculture.

Topics. This historical marker is listed in these topic lists: Animals • Disasters • Environment • Horticulture & Forestry. A significant historical date for this entry is May 18, 1980.

Location. 46° 15.014′ N, 122° 8.239′ W. Marker is in Gifford Pinchot National Forest, Washington, in Skamania County. Marker is on Forest Road NF-99, 16 miles Forest Road NF-25. Marker is located at the Windy Ridge Viewpoint in Mount St. Helens National Volcanic Monument. Touch for map. Marker is in this post office area: Cougar WA 98616, United States of America. Touch for directions.

Other nearby markers. At least 6 other markers are within 7 miles of this marker, measured as the crow flies. Mount St. Helens (approx. 0.9 miles away); Hearts of Volcanoes Beat Beneath Peaceful Facades

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(approx. 0.9 miles away); Survivors Create Spectacular Change (approx. 2.3 miles away); The Earth’s Monumental Power (approx. 5.4 miles away); Working with Nature to Rebuild an Ecosystem (approx. 5.4 miles away); More Than He Bargained For (approx. 6½ miles away).

Also see . . .
1. Pumice Plain. The Pumice Plain is one of the most spectacular features of the blast zone. Lying between the crater and Johnston Ridge, the plain was in essence sterilized of life after the lateral eruption in May of 1980. The intense heat of the pyroclastic flows killed everything on the plain. Consequently, plant recolonization has been much slower here than other parts of the Blast Zone. (Submitted on October 31, 2020, by Cosmos Mariner of Cape Canaveral, Florida.)

2. Thirty-three active research studies are taking place on land buried in ash. The Pumice Plain on Mount St. Helens is one of the most unique places on Earth, a 6 square mile landscape that was buried in ash during the mountain’s 1980 eruption, where almost no trace of human influence remains. (Submitted on October 31, 2020, by Cosmos Mariner of Cape Canaveral, Florida.)

3. Truman Trail - Pumice Plains. After nearly four decades, the pumice plains are now teeming with life. It’s not unlikely that you’ll catch sight of mountain goats, elk and songbirds as you meander up and down the gentle

Marker detail: Elk image. Click for full size.

Photographed By Charlie Crisafulli, USDA Forest Service

2. Marker detail: Elk

Days after the eruption, elk tramped across the Pumice Plain. Their droppings fertilized and seeded the ground. At least 15 species of plants growing on the plain today were transported in their intestinal tracks. Elk's hooves break up the ash and pumice crust; forming sprouting sites for new plants. They also eat and trample plants, slowing the recovery.

moss-covered hills. (Submitted on October 31, 2020, by Cosmos Mariner of Cape Canaveral, Florida.)

Marker detail: Lupines image. Click for full size.

Courtesy Gary Braasch Photography

3. Marker detail: Lupines

A year after the eruption, a tiny lupine plant sprouted on the Pumice Plain. It reproduced at an astounding rate, blanketing volcanic rock. Bacteria on lupine roots manufacture nitrogen, providing this fertilizer to the plant. Leaves caught and held wind-blown seeds, and added nutrients to the pumice when they died.

Marker detail: Pocket Gophers image. Click for full size.

Photographed By Charlie Crisafulli, USDA Forest Service

4. Marker detail: Pocket Gophers

These mammals excavate tunnels across the plain as they forage for plant roots. Their damp tunnels provide shelter for frogs, newts, and salamanders as they travel across the sun-baked valley. Gopher waste helped fertilize establishing plants.

Marker detail: Insects and Spiders image. Click for full size.

Photographed By Ross Hutchins, Mississippi Entomological Museum

5. Marker detail: Insects and Spiders

Millions of insects fly, hop and parachute onto the Pumice Plain. Spiders spin silk that catches the wind, transporting them as far as 30 miles. Insect carcasses add nutrients to the Pumice Plain, up to 80 pounds per acre, per year.

Photographed By Cosmos Mariner, July 17, 2015

6. The Pumice Plain Marker

(Mount St. Helens pumice plain in background)

Mount St. Helens image. Click for full size.

Photographed By Cosmos Mariner, July 17, 2015

7. Mount St. Helens

(view from marker)

Windy Ridge Viewpoint image. Click for full size.

Photographed By Cosmos Mariner, July 17, 2015

8. Windy Ridge Viewpoint

(turn here to access marker)

Credits. This page was last revised on October 31, 2020. It was originally submitted on October 30, 2020, by Cosmos Mariner of Cape Canaveral, Florida. This page has been viewed 334 times since then and 85 times this year. Photos: 1, 2, 3, 4, 5, 6, 7, 8. submitted on October 31, 2020, by Cosmos Mariner of Cape Canaveral, Florida.