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A woman stands amongst a grove of a Giant Sequoia trees in the Sequoia National Park in Central California on October 11, 2009.
A giant Sequoia tree planted more than 130 years ago by naturalist John Muir in the orchard of his home in the northern California town of Martinez is in danger.
The tree is now 70 feet tall and has been infected with fatal fungus, so arborists are trying to clone it.
For more on this, we're joined by Keith Park of the John Muir National Historic Site.