They're a wooly cinnamon color. For this species, a spore-bearing frond grows from the rhizome separate from sterile fronds. Sporophytes have separate fertile and sterile pinnate fronds are covered with thick hairs when immature.
Some hairs are still present on fertile fronds at maturity.
There will also be no trace of sori. Remember this plant is found in particular habitats. Cinnamon fern occurs in North America from Newfoundland to western Ontario and south to the Gulf States and New Mexico. Found on poorly drained low ground and in thickets, wet marshy woods, swamps, ditches, and streambanks. It is generally found in ombrotrophic bogs, but it also grows on minerotrophic wooded island hummocks in peatlands.