By Shelby Sebens
(Reuters) - A new study to determine the age of iconic old-growth redwoods in California's Muir Woods has revealed that one of the tallest and most famous trees in the forest is much younger than many assumed given its massive size, scientists said on Tuesday.
Tree 76, so named because it towers 76 meters or 249 feet above the forest floor, is 777 years old, much younger than the oldest known redwood, according to a study by Humboldt State University, which has long been working with conservation group Save the Redwoods League on the impact of climate change on the trees.
"Tree 76 is one of the larger trees that you can walk near so I think people have been guessing about its age for a long time," Save the Redwoods League Science Director Emily Burns said. "We know Redwoods can live quite a long time. The oldest one that we know of is 2,500 years old."
Redwoods include the tallest living trees on Earth.
Though visitors often ask the age of the tree in Muir Woods, located in the same area that famously played host to a 1945 United Nations meeting, this is the first time scientists can give an accurate answer, Burns said.
Researchers from Humboldt were able to climb the massive trees last year to take various pencil thin core samples that they can use to compare and determine not only the age of the tree but the structure and biodiversity as well.
The research is aimed at better understanding how climate change and major weather events such as drought impacted the redwoods in the past and how they might be affected in the future.
Burns said that large trees are often thought of as being at least 1,500 years old, but that smaller trees can be much older than the giant redwoods, named for the reddish color of their bark.
"Age and size don't correlate well," Burns said, adding that this is the first time the age of 76 age has been determined by scientists.
Humboldt State University researcher Allyson Carroll, an author of the study, said that previously researchers could not get the age of a standing tree from the ground, primarily because they cannot reach the center of the tree from the ground.
Using the core samples taken from higher up and a formula developed by the researchers, they can now determine a tree's age as well as its climate history, she said.
(Editing by Cynthia Johnston and Sandra Maler)