Lookout! It Is Still Technically Active

Geological Background

Actually geologically speaking, the area around Lassen Peak, the southernmost volcano in the Cascade range from Canada, is young. The Cascades are part of the "Ring of Fire", the edges of earth crust --tectonic plates , that goes around the Pacific Rim.

The east coast metamorphic rocks as in Acadia National Park are half a billion years old, but these are remnants of a 600,000 year old statovolcano, Mt. Tehama, whose caldera had a leak, so no lake like the one on Crater Lake. Lava Beds National Monument, also in California, is another part of the huge geographic entity. But the eleven mile edges of this huge sunken mountain top are the mountains: Brokeoff, Pilot, Pinnacle, and Conard. Like the planet Vulcan, this not only has live (dormant) volcanoes, but pools of boiling water, bubbling mud pots, steam fumeroles, and hot springs, many venting sulphur. These are in the geothermal area that includes fascinations like Sulphur Works, huge Bumpass Hell, Little Hot Springs Valley, Devil's Kitchen, Boiling Springs Lake, and Terminal Geyser.

In fact it is the site of the last continental U.S. volcanic eruption until Mt. St. Helen stole its thunder. But Lassen, as one of Tehama's northern flank's vent, is the world's biggest plug dome volcano, 2000 feet more added to the serration to a total of 10,457 feet in elevation. Cinder Cone in the park is a volcano created in the eighteen hundreds.

The Eruption of 1915

The Lassen Peak actually started in the spring of 1914 but did not really get rambunctious until the following dates in May, the 19th and 22th. This last volcanic blast (a term coined by Gorshokov in 1963 --meaning radiating damaging force) that formed substantial lahars (mudflows and dacite lave flows was documented by local eyewitnesses. The sediment is called a "blast deposit." A geologist Diller came to the site a year later observed that the ensuing steam blast melted leftover spring's snow and caused the massive lahar on May 20. Around ten years later Day and Allen theorized that tephra deposits caused the mudflow (because no fallen trees). Of course these studies however conflicting are essentiall in understanding will this all go bang again?

Other Natural Features

The 150 square mile park in a very lightly populated area has one hundred and fifty miles of trails (seventeen of which are the Pacific Crest Trail). Besides going to mountain tops and witnessing sights and sounds that come out of Hades itself beneath, one can hike through old growth forests, or alpine tundra, refreshed by rushing streams that even spill magnificantly as waterfalls. You can see snow in summer.


Of course the first to enjoy the region were the Native Americans. Before the Europeans arrived in the seventeenth and eighteenth centuries there were over a hundred different tribes with almost two dozen varying tongues who came first from the ice bridges from the two last Ice Ages seventy millenia ago. They have documented the locations of the populous and surviving Maidu, and the existing peaceful Atsugewi. The Yana and Yahi indigenous peoples were wiped out battling the homesteaders in the late 19th century.

The Story of Ishi

One of the most interesting and touching tales is the improbable story of the last of the Yahi. A lone survivor came out of the woods near Oroville, California, in 1911, and his university anthropologist benefactors named the maverick Indian, Ishi (Yahi for man). Before he died of tuberculosis in 1916 he shared his heritage, and gained love and honor in return.

Conquistadors and Explorers

Spanish colonialists of course had been in California in the 18th century, but Don Luis Aruguello arrived at what he called San Jose in 1821. The English Hudson Bay Company man, Peter Skene Ogden beat him as being the first European to the area, and he when he ran across the Sastise Indians around a mountain seventy mile north of Lassen he purported to have named it Mt. Shasta. Our mountain was given a second name, Mt. Joseph by trapper Jedidiah Smith, and a U.S. exploration team renamed it Mt. Saint Joseph in 1841.

The Namesake

Peter Lassen, a Danish immigrant, in the 1840's blazed a trail (eventually replaced) for westward settlers, and he is considered instrumental in the formation of creating successful settlement of Northern California. He is honored by putting his name to the mountain, the park, and the forests.

The Experts

The first geological survey started in 1863, and this where the first reports of the mega volcanic source of Mount Tehema. The sizeable geothermal feature was discovered by Kendal Vanhook Bumpass, and in 1864 the "Hell" has his name. The area was made a National Park in 1916, especially to preserve its volcanic uniqueness, and especially for future study.

Flora and Fauna

Starting at the top, around 8000 feet one can find the subalpine treeless and almost animal-less zone. Then where the treeline begins, one finds the wind twisted whitebark pines. There are the plants adapted to the rugged system, skunk leaf polemonium, buckwheat, dwarf hulsea, golden drabe, smelowskia, (the latter two unique to this environment) phacelia[, and fremont groundsel. Then, in between the mountain hemlock, the Indian paintbrush, heath, lupine, spirea and other rarities delight the hardy hiker. Your companion up at this altitude may be a wolverine, a flying falcon, soaring golden eagle, or a hovering hawk. Coming down another 1500 feet and the old growth red fir has grouse, rock wrens, woodpeckers, thrush and hares. Western White pine, join mountain hemlock and lodgepole pine along with flying squirrels. Also dependent on these protected trees is the Spotted Owl.

Below 6000 feet and amongst the ponderosa, Jeffrey, and sugar pines, and white fir is gooseberry, manzanita and ceanothus crawling with rubber boas and garter snakes, and besides the chipmunks, ground squirrels, blacktailed deer, foxes, and skunks there will be martens, and owls -- pygmy and great horned. Lower down When you are around Manzanita Lake and its namesake plant and thick chinquapin you will be joining mountain lions and coyotes and their food, rabbits and deer. Summer sparkles with wildflowers: pyrola, violets, coralroot, and iris visited also by the tortoise shell butterflies (at the heights).

This noder drank the water when he was a lad of 11 in 1960. The young tourist was sick trailside trying to get to the hot springs.


North on I-5 from Sacramento. Right on 36 at Red Bluff, north on 89 at around Mill Creek.

Source: National Park Service
Shasta Travel Center
Lassen Geological site

U.S. National Parks and Monuments

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