Rhizocarpon geographicum Map Lichen on small summit before Lundin Peak See an interesting article on the use of lichens to measure the date of deposition. www.blackwellpublishing.com/Microbiology/pdfs/lichens.pdf yellow-green islands are areolae black fungal hypothallus at the margin. Red Pass and Lundin Peak Hike 27 July 06 King County, Washington, USA i072706 052