This time last week, my intrepid research colleagues were ascending up into the tall trees of Cathedral Grove at Muir Woods National Monument. This historic first climb was part of BioBlitz 2014, a massive effort throughout the Golden Gate National Recreation Area to identify as many species as possible over a 24-hour period.

Rangers diverted park visitors up onto the Hillslope trail which provides a canopy view into the Grove, while the research team rigged and climbed the trees to discover how tall the trees actually are and find out what lives up in the canopy. Stephen Sillett and Marie Antoine from Humboldt State University climbed up a 76m (249 ft) coast redwood and found more than 40 species of lichen covering the tree trunk and ancient branches. This redwood is part of an ancient cluster of trees which are likely granddaughters or great-granddaughters of a single redwood that lived in this valley hundreds of thousands of years ago.

Not far away, Cameron Williams and Rikke Reese Næsborg from U.C. Berkeley climbed up a magnificent and ancient Douglas fir with large, twisting branches. This 70m (230 ft) fir had 57 species of lichen.

I am so grateful for the Save the Redwoods League, National Park Service, National Geographic, the Golden Gate National Parks Conservancy, and the San Francisco Foundation for making this unprecedented expedition possible!