Photo Tour: Eucalyptus regnans

Australia has the tallest trees in the Southern Hemisphere, including dozens of Eucalyptus species over 200 feet and at least one over 300 feet. Known as mountain ash in Victoria and swamp gum in Tasmania, Eucalyptus regnans is the undisputed tallest flowering plant in the world. Rumors of its extraordinary height abound, and there have been well-publicized claims of several trees over 400 feet that were either logged or burned since European settlement. The highest credible report is of a 375-foot-tall tree felled near the Victorian town of Thorpdale in the late 19th century. Today the tallest living individual is a Tasmanian tree 327 feet to a thriving, reiterated top. Its highest leaf stands 25 feet above the highest dead piece of the original crown. Based on the dead diameter at this height, we estimate the tree was 340 feet tall in its prime. We have been studying these amazing trees since 2002.

Other Photo Tours

Doing Canopy Science »

How exactly do scientists explore the tops of the world's tallest trees? Here's a slideshow detailing some of the climbing techniques used in canopy research at Humboldt State University.

Redwood, Sequoia sempervirens »

These five photo tours detail the world's tallest tree species, coast redwood (Sequoia sempervirens), the crown structure of redwood trees, views from old-growth forest canopies, and the unique plants and animals that live hundreds of feet above the ground.

Giant Sequoia, Sequoiadendron giganteum »

This photo tour explores my work with Sequoiadendron giganteum, the giant sequoia. This species is confined to California's Sierra Nevada, where they reach sizes greater than the biggest living coast redwoods and ages up to 3200 years.

Douglas-fir, Pseudotsuga menziesii »

Before logging took its toll on the Douglas-fir forests of British Columbia, Washington, and Oregon, specimens over 400 feet tall were measured. Today the highest concentration of Douglas-firs over 300 feet tall reside in northwestern California amidst the redwoods, as shown in this photo tour.

Sitka spruce, Picea sitchensis »

Targeted by loggers for its wood, whose strength to weight ratio is among the highest on Earth, very little old-growth Sitka spruce forest remains. As with Douglas-fir, the highest concentration of Sitka spruce over 300 feet now resides in northwestern California amidst the redwoods.