Recent research done by Steve Sillett of Humboldt State University and his colleagues suggests that the President Tree in the Giant Forest area of Sequoia National Park in California is the world’s second-largest giant sequoia tree. Yet, the National Park Service lists it as the third-largest giant sequoia tree. Why the difference?
According to Nate Stephenson, a research ecologist with the U.S. Geological Survey who has studied giant sequoias for over 30 years at Sequoia and Kings Canyon National Parks:
“Because branch volume is quite difficult to measure accurately, size rankings for the biggest sequoias usually have been based upon trunk volume only. By trunk volume, the General Grant Tree is second largest and the President Tree is the third largest. If you include branches, the order switches.
But, no matter which measure of size you choose, both trees are awe-inspiring!”
Previously, the President Tree and many other giant sequoia trees were measured by Wendell D. Flint, as published in his book, To Find the Biggest Tree (2002). Because living sequoias add new growth each year but can also suffer losses due to breakage, tree dimensions change constantly.
Sequoia and Kings Canyon National Parks continues to maintain its list of the 30 largest giant sequoias by trunk volume only. On this list, the President Tree is ranked the third-largest giant sequoia, with a note that if branches are included it is the second largest.
The list below was compiled from Wendell’s Flint’s boo, To Find the Biggest Tree (2002), and was revised this December by National Park Service and U.S. Geological Survey Staff. There are several systems for measuring trees. This list is organized by the volume of the tree’s trunk only – the amount of space occupied by the trunk. It does not include the volume of branches, foliage, or roots. The hollow spaces left by rot or fire scars are counted as a solid.
Because living sequoias add new growth each year but can also suffer losses due to breakate or fire, tree dimensions change constantly. Until 2003, the Washington Tree in Giant Forest (Sequoia National Park) was the second-largest sequoia. After being reduced by fire, it no longer ranks among the top 30.
Scientists from Humboldt State University measured the President Tree extensively in 2011-12. They discovered that if branch volume is included with trunk volume, the President Tree is the second largest and the Grant Tree is the third largest.