Lassen County
Visitor Guide
CA 0
View Website
Spattercone Trail  

Long River of Lava
Welcome to Spattercone Trail. This 1.5 mile loop trail will take you to the origin of the recent Hat Creek Lava Flow, an area with many spattercones and associated volcanic features.

CAUTION. Some portions of the trail are steep. Due to hot, dry conditions, it is best to take this hike in the early morning or late afternoon. Carry water!

Stay on maintained trails! Some of the rock outcroppings and cave-ins are unstable and dangerous.

You are standing on the edge of the Hat Creek Lava Flow. About 20,000 - 30,000 years ago, large volumes of fluid lava poured from a series of fissures (cracks in the earth) and flowed northward for 16 miles, covering the floor of the Hat Creek Valley. The spatter cones, further up the trail, mark the approximate locations of these fissures.

Rocks with Holes
The rocks here and all along the trail are basalt, a fine grained dark volcanic rock rich in iron and magnesium Notice the small holes in the rocks. This particular kind of rock is called vesicular basalt (from the Latin vesicular or "little bladder"), because of the small holes. During solidification, trapped gas bubbles expand within the lava and escape into the atmosphere, leaving behind the small holes or cavities (vesicles).

Pollution Indicators
Look closely at these rocks; can you see any small, crusty green, grey and orange specs or blotches? These are lichens - a type of fungus that grows in combination with algae, forming the small organisms that you see here. The bright yellowish-green growth that you see on nearby trees is a larger lichen called Staghorn Lichen. Lichens are sensitive to air pollution and are usually not found where air pollution levels are high. Some lichen species are even used to monitor changes in air quality. Based on what you observe about the lichen here, do you think the air here is fairly clean?

Who Lives Here?
Have you noticed any wildlife along the trail? Birds commonly seen along the trail include Ravens, Steller's Jays, Red-tailed Hawks, and Rufous-sided Towhees.

You'll be crossing the Pacific Crest Trail as you go straight ahead. After crossing, go left at the trail fork.

Puzzle Rock
Lava from the Hat Creek Flow was very hot (about 2,000 degrees F) when it poured out of the fissures. Fast hot flows such as this one are called Pahoehoe (Hawaiian word; pronounced pah-hoy-hoy) flows. This basaltic pahoehoe lava looks blocky, due to jointing. Jointing is a system of vertical cracks that form the lava as it cools and contracts, often leaving the lava separated into blocks and columns.

Hardy Individuals
As you can see, some plants do quite well on the flow's dry, thin soils. Lava joints provide spaces for plants to anchor their roots as do pockets of deeper soil. The brush here is dominated by Bitterbrush and Greenleaf Manzanita. Bitterbrush has small, soft, pale green leaves and grayish brown bark. When in bloom, its flowers are pale yellow. It is a favorite food for deer.

Greenleaf Manzanita can be identified by its roundish, leathery, bright-green leaves and its smooth, reddish bark. Manzanita seeds were used by local Atsugewi Indians to make flour. Ripe, red berries were eaten as a fruit, while unripe, green berries were used to make tea and cider.

Hollow Worlds
As the lava flowed downhill it developed many fingers that soon crusted over, restricting the inner flow to a "tunnel system." As the inner liquid lava continued its course downhill, it sometimes flowed out of these hardened shells, draining them, and leaving behind many hollow tubes or caves. Tube openings, such as this one, are caused when the tube's roof of hardened lava collapses.

Loose lava rocks can be hazardous

Lava Tube Locators
These clusters of small trees are "Curleaf Mountain-mahogany," a member of the rose family. This tree tends to grow on or near lava tubes, as does green moss, often indicating the presence of unseen hollow tubes below the surface.

Could the ground you're standing on be hollow underneath?

Giant Steps
Notice the three collapses heading downhill in a step-like manner. Prior to collapsing, this was one lava tube.

Cinder Cones
The large "symmetrical" volcano in front of you is Sugarloaf Peak, a young lava cone, probably less than 10,000 years old. Sugarloaf Peak is topped with a cinder cone. To the left, at its base, is another cinder cone. Cinder Cones are small volcanic cones built entirely of fragmental materials (ash, cinder, etc.) which was explosively shot from their vents. There's

Shasta Cascade Wonderland Association
1699 HWY 273, Anderson, CA 96007 | (P) 530-365-7500 | (F) 530-365-1258