Pellaea glabella fronds are relatively small with blades
often less than 20 cm long. The blade is pinnate toward the tip
and 1- or 2-pinnate at the base. Sporangia are borne under the
inrolled margins of the blade segments. The red/purple rachis
is glabrous on the adaxial (upper) surface, unlike the densely
pubescent adaxial surface of the similar P. atropurpurea.
Four subspecies have been recognized in the recent Flora of North
America, only one of which, subspecies glabella occurs
P. glabella var glabella ranges from southern Quebec
to Virginia and Kentucky, west to Ontario, Minnesota and northeastern
Oklahoma. In Wisconsin it is known across the southern counties,
north along the Missisippi River to Polk County in the west and
in the east into Door County. It grows primarily on limestone.