Fronds of Gymnocarpium dryopteris are usually less than
40 cm long (12-42). The blade ranges from 3-14 cm long and is
clearly shorter than the stipe. The blade is broadly triangular,
2- pinnate-pinnatifid and ternate (divided into three roughly
equal branches at the base). Sori are round, located on the underside
of the blade and there is no indusium. The horizontal stems are
elongate so leaves are not densely aggregated. The blades are
not glandular, or occasionally there are a few glands on the abaxial
(lower) surface. The closely-related species, G. robertianum
and G. jessoense differ in the presence of more conspicuously
glandular blades, but can be difficult to distinguish.
G. dryopteris ranges from Alaska fully across Canada,
south to West Virginia, Ohio and Minnesota. It is also found in
the northwestern U.S. and at scattered locations in several other
western states and in the Great Plains. It is found nearly throughout
Wisconsin, except for a few counties in the southeast, but it
is more common in the northern half of the state. Habitats are
mostly cool, coniferous or mixed forests, including conifer swamps.
Fronds wilt extremely rapidly if picked.
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