An old growth redwood forest is nature’s cathedral. Light filters through the giant trees bathing the ferns and mosses below in a primordial green glow.

In the canopy of a 300-foot old-growth coast redwood, the going gets weird. Mosses, lichens, fern mats, even other trees all grow in the canopy soil.

The Brotherhood Tree, a massive redwood in Klamath, California, is host to a complex wildlife habitat and its canopy is full of surprises for those who venture aloft. Bats flutter out into the faces of climbers and hundreds of birds circle territorially above. […]