B. Strobe No description specified. 1-2 (2 Records) Documents NPS Unga Island Petrified Tree National Natural Landmark Unga Island, Alaska, Mapping & Data Collection (1996) NPS Unga Island Petrified Tree National Natural Landmark Unga Island, Alaska, Zachary Bay Mapping and Data Collection Project, Report for Arch Field Permit 98-2 (1998)