A lichen is composed of one or more (out of tens of thousands of) species of fungi living with one or more (out of hundreds of) species of algae and possibly one (of fewer than one hundred of) cyanobacterial species. Combinations of those three taxa have created characteristics that defy human-made rules to classify them. It would take longer than a human lifetime to become an expert in all the species of lichens. It would certainly take a much larger book to describe all the variable characteristics that arise due to those combinations. While thin-layer chromatography (TLC) procedures and molecular DNA studies are being used to sort out lichen relationships and lineages of lichen taxa, they are beyond the scope of a general introductory guide. Lichen Study Guide for Oklahoma and Surrounding States is intended to help the user begin the journey of learning about lichens based on ecological, morphological, and chemical characteristics of species found in the Southern Great Plains region.
Sheila A. Strawn holds a B.S. in Biology and a M.Ed. summa cum laude in Adult Education from the University of Central Oklahoma. Her Ph.D. is in grassland ecology from the University of Oklahoma. She has edited the Oklahoma Native Plant Record since its inception in 2001 and has studied lichens for over 15 years.