California State Parks Begins Study of Fallen, Iconic "Tunnel Tree" in Calaveras Big Trees State Park

Contact: Adeline Yee I California State Parks I (916) 651-8725

Contact: Ashley Boarman I Save the Redwoods League I (415) 359-2312 

ARNOLD, Calif. – Marking one year since the famous Pioneer Cabin Tunnel Tree toppled, California State Parks, Save the Redwoods League and Humboldt State University today announced plans to use the fallen sequoia to study the tree’s life history and gather historic climate-related information for the surrounding area. The information will help California State Parks better manage the existing groves of redwood trees. The giant sequoia is the largest tree species in the world, with some trees reaching a diameter of 36 feet.

Located within Calaveras Big Trees State Park within a relatively large sequoia grove containing more than 150 specimens estimated to be 2,000 years old, the Pioneer Cabin Tree was one of California’s oldest tourist attractions and a beloved specimen of a rare California native species. A combination of trunk and root decay and storm water runoff appears to have brought the giant sequoia down at its base on January 8, 2017, shattering it and a nearby cedar tree. The Pioneer Cabin Tree stood approximately 205 feet tall and was more than 19 feet in diameter (measured six feet from the ground).

“California’s state parks are endowed with globally, nationally and regionally significant natural resources,” said Heather Reith, Senior Environmental Scientist at Calaveras Big Trees State Park. “Studying the Pioneer Cabin Tree will reveal valuable information about drought, rainfall, historic fire intervals and other climate changes over time that will assist in the long term and sustainable stewardship of these treasured giant sequoias.”

Since the tree fell last year, California State Parks has worked with Save the Redwoods League and Humboldt State University Dendrochronologist Allyson Carroll, a scientist who studies tree rings to comprehend past events, to create a plan to study the tree. The first step in the study of the sequoia involved removing approximately a 7 ½’ by 3 ½’ piece of the tree using a large saw. The section took about ten hours to remove and was then relocated to a warm and dry building within the park. The specimen will take at least six months to dry. Once drying is complete, Save the Redwoods League will sand and prepare the piece for Dendrochronologist Carroll to begin her study of the tree’s rings.

“This iconic ‘tunnel tree’—thousands of years old when it died—has one more story to tell, and it’s all about the dynamic environment that it has occupied throughout its long life,” said Paul Ringgold, Chief Program Officer at Save the Redwoods League. “With the last remaining giant sequoia living in small, scattered groves along California’s Sierra Nevada, it’s important for us to know as much as we can about their life history, so we can all better protect these ancient giants.”

After Carroll has collected and recorded all information, the removed portion of the tree will remain in the park as part of an interpretive display that State Parks and the League will collaboratively design, where its history can live on.

Calaveras Big Trees State Park became a state park in 1931 to preserve the North Grove of giant sequoias. Lightning strikes in the 1800s hollowed out the Pioneer Cabin Tree’s base and later knocked off its crown and opened up its side. In 1881, the Pioneer Cabin Tree base was squared off and enlarged. Similar to Big Stump, the base of the 1850 Discovery Tree at Calaveras Big Trees State Park, the Pioneer Cabin Tree helped visitors experience the enormous size of the ancient sequoias. For 60 years, tourists rode horses and carriages through the Pioneer Cabin Tree, and in the 1920s, automobiles passed through it. Thousands of visitors posed for photos at the tree.

The Pioneer Cabin Tree before it fell (left) and recently when a piece was cut to be studied (right).

Click here to visit a full gallery of photos of the Pioneer Cabin Tree and Calaveras Big Trees State Park.


About the Famous Giant Sequoias

The Pioneer Cabin Tree was one of the last of the historic tunnel trees in the Sierra. This giant sequoia fell in January 2017 after a series of heavy storms. The Palace Hotel Tree and Smith Cabin Tree remain standing in the more remote South Grove Nature Preserve at Calaveras Big Trees State Park. The California Tree in Yosemite’s Mariposa Grove of Giant Sequoias and three coast redwood tunnel trees in northwestern California are other storied sequoias in public parks.

Save the Redwoods League
One of the nation’s oldest conservation organizations, Save the Redwoods League has been protecting and restoring redwood forests since 1918, connecting generations of visitors with the beauty and serenity of the redwood forest. Our 19,000 supporters have enabled the League to protect more than 200,000 acres of irreplaceable forest in 66 state, national and local parks and reserves. For more information, go to

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