After a hellish hike in the wilderness above Yucaipa in the San Bernardino Mountains on a recent weekday, seven naturalists with cameras, measuring tape and lasers entered the shade of a gargantuan oak tree and looked up at its gnarled branches, their eyes wide with anticipation.

The Wildlands Conservancy members had come to take precise measurements of what they believed could be the largest canyon live oak tree in existence and, perhaps, the largest oak of any species in the country.

PHOTOS: Giant oak in the San Bernardino Mountains



“Hell of a tree,” whispered Geena Burgess.

April Sall spread her arms wide and simply smiled.

Evan Welsh, who discovered the tree in early July, started unpacking an assortment of surveying equipment.

Earlier this month, Welsh took initial measurements that suggested the tree was eligible for certification by the American Forest’s National Big Tree Program as the nation’s “champion” oak.

Nominating a tree with record-breaking potential requires three measurements: trunk circumference in inches; height in feet and average crown spread in feet. Total points for a contender are determined by using this calculation: trunk circumference in inches, plus height in feet, plus 1/4 the average crown spread in feet.

With 628 points, a 153-foot-tall valley oak in Mendocino County had been regarded as the nation’s undisputed champion since the 1980s. However, that tree’s status was reduced to 520 points earlier this year after American Forests arborists determined that its measurements had been inflated.

On Thursday, the Wildlands Conservancy forwarded a formal nomination for “champion tree status,” along with measurements to back it up, to Michael Taylor, American Forests’ California champion tree coordinator.

On Friday, David Myers, executive director of the conservancy, telephoned Taylor to confirm he had received the information. That’s when he learned that the Mendocino County tree had been demoted.

“I verified the tree the same day it was nominated by the Wildlands Conservancy,” Taylor said. “It is the champion oak. It has no equal.”

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--Louis Sahagun

Photo: Wildlands Conservancy naturalists and volunteers climb on the champion oak. Credit: Irfan Khan / Los Angeles Times