Measurement of Hyperion, the tallest tree in the worldAs explained on this page, the world's tallest tree is a coast redwood (Sequoia sempervirens) named Hyperion. This tree is 115.55 m (379.1 feet) tall! This enormous tree was only discovered in August 2006 in a remote part of the Redwood National Park, California, by naturalists Chris Atkins and Michael Taylor.
The first preliminary measurements were made with professional laser measurement equipment based on goniometry. In September 2006 the tree was remeasured for the Guiness Book of Records by Steve Sillett. This was done in the most accurate way: he climbed to the top of the tree to drop a tape from there straight to the ground. This tape drop was filmed for National Geographic.
You can watch this footage on the website of National Geograhic or you can watch it directly here.
During the first part of the report you can see a glimpse of the famous Wawona Tunnel Tree in Yosemite National Park, together with some horse riders riding thought the tree. But this tree, that died in 1969 as a result of the construction of the tunnel, is a specimen of the giant sequoia (Sequoiadendron giganteum), while Hyperion is a coast redwood (Sequoia sempervirens). It's strange to see that even National Geographic is mixing these species up, maybe because there are also a number of similar, smaller "tunnel trees", that are actually coast redwoods.
A student of Steve Sillett, named Jim Spickler, also made a movie about the climbing of the world's tallest tree.