The fronds of Polypodium virginianum are monomorphic
(fertile and sterile fronds are similar in appearance), the
blades are pinnatifid, less than 7 cm wide and the sori are round.
That combination of characters is unique in our flora. Fronds
may be up to 40 cm long, but are often less than 25 cm, and they are "evergreen", remaining green throughout our northern winter. The blades may shrivel up under dry conditions, as shown in the photo at extreme right, but
they have a remarkable ability to recover their original appearance when they are
rehydrated, and that is the basis for the common name of "resurrection
fern". Severe drought for a prolonged period will kill these plants, but they can tolerate drought conditions which would be fatal for most other ferns.
P. virginianum ranges from Labrador to Georgia, west to
Alberta, Minnesota and Arkansas. It is found throughout Wisconsin,
although it appears to be uncommon in the southeastern counties.
Habitat is often on rocks of various types, or if on soil then
usually on steep slopes.
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