According to Wiki, northern beechfern is a terrestrial fern that can also be epipetric. So why not just say they can grow on rocks? Because if you want to be more precise, and communicate in a word instead of a sentence, epipetric does the job. It means growing on the surface of the rock. If it was in crevices, it would be endolithic. So, it eases communication. But only if the person that hears the word knows what it means. Otherwise, like me, they spend five minutes looking up epipetric, and another however long reading all the other interesting stuff that leads to. Then you can spend however long carrying on like I'm doing now. Gotta love all that scientific jargon! Northern beechfern grows in AK, CO, CT, IA, ID, IL, MA, MD, ME, MI, MN, MT, NC, NH, NJ, NY, OH, OR, PA, RI, TN, VT, WA, WI, WV, through Canada, and on GL and SPM. Baraga CO MI, 7/13/14. Woodfern family, Dryopteridaceae.