Photo 61446690, (c) Joe Walewski, some rights reserved (CC BY-NC), uploaded by Joe Walewski

Attribution © Joe Walewski some rights reserved Uploaded by jwalewski Source iNaturalist Associated observations Photos / Sounds What Concentric Boulder Lichen (Porpidia crustulata) Observer jwalewski Date February 14, 2020 09:04 AM CST Place Cook, Minnesota, United States (Google, OSM) Date Added February 14, 2020 12:51 PM CST 2 IDs Research Grade View Sizes small medium large original