Lichen Tuesdays!


by Kim Traverse, PSMS  President

Lichen study might pass for exoteric if it weren’t that lichens are almost everywhere- on the sidewalks and streets we use daily, on the walls and trunks of trees that we walk past, clinging to the branches of those trees and on shrubs. From the shore to the top of mountain peaks, lichens coat the rocks and sometimes cover the ground. They are part of every ecosystem except the deep sea and can live in the harshest places on the planet- the driest, the coldest, the hottest- at least one grows underwater.

The Seattle Lichen Guild has been meeting regularly since 1987 and provides a convenient place for those interested in the study of Lichen to share information and enthusiasm. Occasional outings to survey and collect get us out of the lab and every meeting layers conversations about Lichens, Mosses, the tiny Fungi that interact with them, current nomenclature and discoveries, and smatterings of the other sciences and literature. Dr. Katherine Glew is the Scientific Advisor to the Guild and brings a wealth of information and field experience to meetings which are held in the lab (room 444) Hitchcock Hall on the UW campus. 1605 NE Pacific Ave, a ten-minute walk from the Husky Stadium station of the Light Rail.

Lichen are symbiotic composite organisms that consist of a fungus, an algal photobiont partner (a green algae), and/or a cyanobacterial photobiont partner. This composite organism is named for its most variable partner- the fungi. There are tens of thousands of fungi that lichenize; most are Ascomycetes but there are also some Basidiomycetes. The photobiont makes food (sugars) from air and sunlight via photosynthesis and shares its food with the fungus which in turn provides a protective place for the photobiont to grow. The fungi provide the attachment to substrates, moderate moisture and provide protection from ultraviolet rays. Some of the photobionts (such as Nostoc and Trentepohlia) can be free living but virtually none of the fungi exist in the non-lichenized state.

One of the amazing things about this partnership is that cultured separately, they look so plain and ordinary and don’t even suggest the wild variety of architectures and colors they will create when growing together.

This partial list of common names for some of the lichens suggests that incredible variety. Put ‘lichen’ after each descriptor. Camouflage, Script, Yolk, Reindeer, Horsehair, Christmas, Fairy Barf, Witch’s Hair, Potato-chip, Fog, Lungwort, Toad skin, Frog Pelt, Ticker-tape, Cow-pie, Fringed Moon, British Soldiers, Varnished Tube, Wax-Paper.

For more information including meeting dates contact Dr. Glew at