At first I did not recognize this single frond as being a deer fern. I have tended to associate this type of fern with the clumps of two different frond types (like the one seen on a recent hike to Beaver Lake). This frond is the sterile type. I do not know if it will eventually be joined by others and form a clump of both frond types.
Location: Mt. Verstovia Trail, Sitka, Alaska