SAN FRANCISCO (AP) — An analysis found that the tallest redwood tree in Muir Woods in California is 777 years old — not the 1,500 years once assumed.
The study out of Humboldt State University is the first determination of the age of trees in Muir Woods, north of San Francisco, the San Francisco Chronicle (http://bit.ly/1EOHn2F ) reported Sunday.
The findings mean the 249-foot-tall coast redwood named Tree 76 was born seven centuries later than initially believed and dates back to the start of the Inquisition in the early 13th century.
It also means the oldest and biggest tree found in Muir Woods is just a baby compared with the huge old-growth trees farther north.
San Francisco's Save the Redwoods League is documenting the age, size and tree-ring history of California's old-growth redwood groves as part a statewide project. The plan is to identify tree-ring patterns and figure out how trees react to climate change.
Tree rings are larger during wet years and smaller during dry years.
Tree-ring science was used to document a coast redwood near Crescent City that is 2,520 years old. The oldest giant sequoia, a redwood species that grows in the Sierra Nevada, is 3,240 years old.
Scientists have suggested that the tallest trees in Muir Woods were between 1,200 and 1,500 years old, but the Humboldt study compared the ring size of Tree 76 to a state database and concluded it is 777 years old.
Emily Burns, science director for Save the Redwoods League, told the newspaper the relative youth of the tree and the newly documented ages of two other tall trees mean the grove is probably younger than was believed.
She suggested a fire, flood or some other catastrophe may have struck the area, forcing the forest to regenerate.
Information from: San Francisco Chronicle, http://www.sfgate.com