Community Corner

Save Mount Diablo Scores a Volcanic Dome and Some Very Tall Manzanitas

The nonprofit recently bought a patch of land on the mountain for a pretty affordable price.

Environmental nonprofit Save Mount Diablo bought a parcel of land with what may be the tallest manzanitas around — and a geologically unique volcanic dome.

The 7.4-acre property — bought for a buyer's market bargain of $125,000 — lies on Marsh Creek Road by Marsh Creek just east of Clayton. It's called Marsh Creek-V and it's the sixth parcel the nonprofit bought in the past year for $125,000 or less.

"Marsh Creek-V is especially rich in biodiversity according to their recent findings, including what may be the world’s tallest manzanita," said Ron Brown, Save Mount Diablo's executive director. "Part of the reason for this richness is that the property is a rare volcanic dome with unusual geology."

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The rare red-legged frog could be found on the land crossed by Marsh Creek, a major water source for loal wildlife.

The volcanic dome is composed of igneous rocks from a 165 million-year-old ocean crust, the same rocks that make up the mountain's main peaks, according to Diablo Valley College geology professors Jason Mayfield and Jean Hetherington. There are also pillow basalts created by ancient underwater eruptions and carried to North America by shifting tectonic plates.

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Visit a similar volcanic dome with Save Mount Diablo’s self-guided hike to Lower Perkins Canyon. Save Mount Diablo will guide hikes there on Oct. 8. See the schedule at www.SaveMountDiablo.org.


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