CORRECTION (Published 11/9/2013)

A story about Mount Diablo's purchase of the Curry Canyon Ranch Property incorrectly reported the name of a donor. The donor is the Gordon and Betty Moore Foundation.

MOUNT DIABLO -- A conservation group created to preserve land on this mountain has bought 1,080 acres described as its biggest, priciest and most environmentally rich purchase ever.

The land has lush canyons, dense pine forests, boulders the size of big rigs, grassy hills with big oak trees and a mile-long stretch of steep sandstone cliffs where prairie and peregrine falcons nest in shallow wind caves.

"This is Save Mount Diablo's most important acquisition ever and the most important since North Peak was protected in 1980," said Scott Hein, board president of the conservation group that now owns 2,400 acres on or around the mountain.

The group announced Thursday that it has paid nearly $7.2 million for the Curry Canyon Ranch property on the south and east side of the mountain, 4 miles from Clayton and 3 miles from Danville.

The property also has missing links to four trails in Mt. Diablo State Park that lead from Rock City to the mountain summit.

The purchase prevents potential ranchette development on small parcels that would mar the property's value for wildlife and public recreation, group leaders said.

Save Mount Diablo intends to manage the area as open space until it can turn it over to a park agency such as Mt. Diablo State Park, which surrounds the Curry Canyon Ranch property on three sides.

No date has been set for allowing public use of the property, which is not connected to any public road.

On a recent tour, conservation group leaders drove on a fire road through the land's low-lying grasslands to higher areas with dense stands of knobcone pines, manzanita and other brush.

Off the road were boulders the size of houses.

Jutting 50 to 100 foot above the pine forests were the beige sandstone cliffs, the largest unprotected rock outcropping in Contra Costa County. A mountain lion was photographed on the rocks years ago.

"This is the kind of habitat where the condors will come as they move north from Pinnacles National Park," said Ron Brown, executive director of Save Mount Diablo.

As he drove over a rise, two deer fled from the sport utility vehicle, and a coyote on the other side of the road ran away moments later.

Rugged as the property is, some parts are only a mile away from the upscale Blackhawk community and its lush green golf course.

To the east of the new acquisition are upscale homes on 5-acre ranchettes not far from Morgan Territory Road.

"These small ranchettes are what fragment the property and disrupt the wildlife corridors," Brown said. "First come the ranchettes, then the fences and walls. We're trying to keep these corridors open for the wildlife and as the path for the condor to come back to this area."

Save Mount Diablo has eyed the property for more than four decades.

Group representatives discussed a possible purchase with then property owner Ettore Bertagnolli, a property investor and cattle rancher. Only after his death was a sales deal reached with his estate.

Now Save Mount Diablo has three years to finish paying off the $7.2 million loan it got to finance the purchase.

The California Coastal Conservancy and the Roger and Betty Moore Foundation have committed to providing $4.2 million in grants -- leaving about $3 million more to go.

Those two organizations are known for protecting biological diversity. In this case, surveyors found 733 plant and animal species on the property during a 24-hour survey in 2009.

More than 30 of the species found there are endangered, threatened or given some sort of rare classification, said Seth Adams, Save Mount Diablo's land programs director. Four of the plant types found there only grow on Mount Diablo.

Contact Denis Cuff at 925-943-8267. Follow him at Twitter.com/deniscuff.

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