Mariposa Grove of Giant Sequoias in Yosemite National Park, California

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The giants of Yosemite. Arbor Day

We're celebrating Arbor Day with some of Yosemite's most famous residents, the giant sequoia trees of Mariposa Grove. The day champions the planting and preservation of trees and can trace its roots back more than 150 years. In 1872, Nebraska City News editor Julius Sterling Morton proposed a day for locals to plant trees, and the idea grew and grew. Today all 50 states celebrate Arbor Day, most commonly on the last Friday in April, although different states might observe it on the best dates for tree planting in their area.

Giant sequoias, like the ones on our homepage, have been around for a very long time. Geological evidence suggests that they are the third-longest-lived tree species in the world. There are hundreds of them in Yosemite's Mariposa Grove, including the famous Grizzly Giant, which is estimated to be about 3,000 years old. Let's hope it is around for thousands of Arbor Days to come.