Fiddlehead:

Ferns emerging in early spring are densely covered in woolly hair, which is quickly lost.

Leaves and stems:

Leaves are twice compound, up to 3 feet long, broadly egg-shaped in outline, the “branches” (pinnule) opposite. The leaflets are about 2 inches long and ¾ inch wide, minutely toothed around the edges, with forked veins, blunt tips, somewhat heart-shaped to nearly straight across the base, and little or no stalk. The leaflets are typically alternate with 7 to 10 on each side of a stem. Stems are brown, slender, slightly grooved on the upper side, initially covered with light brown hairs, becoming smooth with maturity.

Spores:

Bead-like capsules containing the spores are attached to a stalk growing at the tip of a leaf (Royal Fern gets its name from this “crown” of capsules at the tip of leaf). The capsules are initially bright green but turn rusty colored then dark brown after releasing the spores.

Notes:

This species doesn't look much like a fern. It can take on a shrub-like appearance and the leaves look similar to a locust tree or a vetch species. Royal fern can be identified by the double compound leaves and clustered spore capsules at the tip of the leaf. There are reportedly 4 or 5 varieties spread across nearly every continent, but only var. spectabilis is recognized in North America, and Minnesota. This has been more recently considered a separate species, Osmunda spectabilis, with O. regalis restricted to Europe, Africa and Asia, though the name change hasn't been accepted in Minnesota (yet).