Keys to Dryopteris species must be read especially carefully, so that pinnae are not confused with pinnules, pinnules on the lower side of a pinna with
those on the upper side, etc.
Frond bipinnate to tripinnate, with the pinnules prominently toothed, the ultimate divisions strongly acuminate and ending in bristle-like tips.
Fronds merely bipinnate or deeply bipinnatifid, the pinnules or primary lobes of the pinnae either not further lobed or, if so, then with the
ultimate divisions blunt; teeth, if present, blunt to ± acuminate but not bristle-tipped.