Old-growth redwood forests represent an extreme in the realm of forest ecology. Their canopies reach extraordinary heights (over 110 m), and individual trees can live for more than two millennia. Ferns, shrubs, and even trees are abundant as epiphytes on large branches of enormous redwood trees. However, these trees do not generally support a diverse and abundant flora of lichens and bryophytes, presumably because their bark peels easily away. In contrast, Sitka spruce, the second largest tree in redwood forests, harbors such non-vascular epiphytes in staggering abundance. Until now, no one has described the assemblage of epiphytic lichens and bryophytes on Sitka spruce. Using rope techniques for canopy access, we have conducted a floristic survey of five tall Sitka spruce trees in Prairie Creek Redwood State Park, CA. We have quantified the distribution and abundance of all non-vascular epiphyte species by sampling a fixed proportion of each tree’s total branch and twig surface area. Biomass estimates were extrapolated to tree totals. Results reveal a high diversity of lichens, including abundant cyanolichens (especially Lobaria pulmonaria) in the upper and outer portions of tree crowns. Thick mats of mosses and liverworts dominate large branches lower in the crowns.

Key words: Picea sitchensis, biomass, bryophytes, lichens, non-vascular epiphytes, Old-growth redwood forest canopy