1. Leaves twice-pinnate, the pinnules clearly stalked; fertile portion terminal on the leaf.
1. Leaves once-pinnate (though pinnae deeply lobed); fertile portions occurring in the middle of the leaves.
All species found in Osmunda
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. March 22, 2019. https://www.michiganflora.net/genus.aspx?id=Osmunda.