They'll Grow Anywhere

Day 163: I have often said that if you hold still for very long in the Pacific Northwe't, you'll find yourself colonized by lichens. Some species can take hold in the very smallest amount of growing medium, in this case, dust and pollen which has collected on the surface of my metal garden gate. At least two species are present here, Parmelia hygrophila dominating at the junction of the two ornamental curls. I have also found the same species growing on the manufactured siding of my house where it found a toehold (rhizine-hold?) in dust trapped in the simulated wood grain. Of course, any organic material is fair game. Lichens have been found on bone, leather and old cloth, and certain species exhibit preferences for one substrate or another. Fortunately for us, they do not seem to have an agenda which includes global domination, although they appear to be fully capable of taking over the world.