Last October, Ira Flatow took a trip to the World Forestry Center in Portland, Oregon, for a daylong exploration of lichen—the fuzzy growths often found on trees, roofs, and gravestones. Ira sat down in front of a sold-out room with Dr. Hannah Prather, postdoctoral researcher and visiting assistant professor of biology at Reed College, and Dr. Jesse Miller, lead botanist for the Washington Natural Heritage Program. From their crucial role in ecosystems as indicators of air quality to their striking colors and forms, we’ve really taken a lichen to these amazing organisms.Transcripts for each segment will be available after the show airs on sciencefriday.com.  Subscribe to this podcast. Plus, to stay updated on all things science, sign up for Science Friday's newsletters.