The Stagg Tree, officially the Amos Alonzo Stagg Tree and formerly known as the Day Tree, is a giant sequoia in Alder Creek Grove in California's Sierra Nevada mountains. It is the fifth largest tree in the world and the tallest giant sequoia south of the Lincoln Tree in Sequoia National Park. The tree features the second largest footprint of any living giant sequoia, measuring 109 ft (33 m) in circumference at ground level, and second only to the Boole Tree. The tree is believed to be over 3,000 years old, making it one of the oldest living giant sequoias.