Botrychium rugulosum has broadly triangular leaves with
width greater than 10 cm broad and born near the ground. The pinnules
are mostly acute in shape and the terminal portion is usually
not fully divided. See a discussion of similar species under B.
B. rugulosum has a limited distribution, ranging from
eastern Minnesota through Wisconsin and Michigan to Vermont and
Ontario. The status of this species in Wisconsin is not yet clear,
but it appears to be rare and has received "special concern"
status. A few records have been reported from the central and
northeastern parts of the state. The identity of some of the reports
from the northwestern counties may be in question. Habitat includes
fields, clearings and young forests.