John D. Olmsted, a naturalist who led efforts to preserve Northern California nature areas, open space and trails, died of liver cancer March 8 at his home in Nevada City, Calif. He was 73.

Inspired by conservationist John Muir, Olmsted spent more than 40 years pursuing his dream of a trans-California hiking trail — roughly paralleling Highway 20 — from Lake Tahoe to the Pacific Ocean. He proposed creating a public-land corridor that would connect a chain of natural landscapes stretching across Northern California.

He set about acquiring parcels by making a down payment to hold the land and scrambling for donations to pay the rest. Many sites later were bought by the state for parkland.

"He wanted to restore California to the wild," said son Alden, a filmmaker who recently completed a documentary about his father. "He saw himself as an 'undeveloper.' "

Olmsted began on the Mendocino coastline, where he acquired a planned motel site in the 1960s that became Jug Handle State Natural Reserve. He went on to buy and transform the old Excelsior mining flume near Nevada City into the Independence Trail, a popular hiking path in the Yuba River Canyon that is accessible to those in wheelchairs.

He later preserved parcels that became the 2,250-acre South Yuba River State Park and its historic centerpiece, the Bridgeport Covered Bridge. He also acquired parkland on Goat Mountain in the Coastal Range near Clear Lake and the Yuba Powerhouse Ranch.

A distant cousin of famed landscape architect Frederick Law Olmsted, John DeVaux Olmsted was born March 2, 1938, in Los Angeles. He earned a master's degree in plant ecology at Pomona College and became education director at Golden Gate Park in San Francisco.

He worked as a naturalist, docent and educator at the Oakland Museum, UC Berkeley Extension and the Mendocino Art Center. He founded two nonprofit groups, the California Institute of Man in Nature and the Sequoya Challenge, to carry out his efforts to acquire and preserve land.

Twice divorced, Olmsted is survived by sons Alden of Los Angeles and Erik of Atlanta, a granddaughter and a brother.

Davila writes for the Sacramento Bee and McClatchy Tribune News Service.

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