Oak fern fronds arise individually from a creeping rhizome rather than in clumps. The 40 cm tall fronds are deciduous, lime-green, broadly triangular, and 2-3 pinnate. The sori are circular lack an indusium, hence the name ("gymno" = naked, "carpium" = fruit). Oak ferns are found in moist woods, on streambanks, and wet cliffs at low to moderate elevations. Contrary to the common name, oak ferns do not grow on or near oak trees.