While taking a break in a spot of sun along Indian River trail recently, I was struck by how white the lichen-covered bark of a riparian stand of red alder (Alnus rubra) appeared in contrast with the greens and browns of the surrounding forest. The bark of alder is naturally gray, but unless they are growing in an especially dense stand or an area with significant air pollution, all except the youngest trees end up with bark that appears white from a distance. Closer inspection reveals several different species of lichen in overlapping growth that completely covers the bark.
