Here is a last roundup of photos from the Grant County field trip - an assortment of ferns other than the Osmunda claytoniana and Athyrium filix-femina highlighted in previous posts - and some notes on identifying them when they're still fiddleheads. Above is Asplenium platyneuron, the Ebony Spleenwort, which was long past fiddlehead stage when we saw it, as was this Botrychium:
The following two photos are Dryopteris marginalis, the Marginal Woodfern. It is easy to tell this one when it's still small and unfurled because of the distinctive scales, which are a golden brown color. Most Dryopteris have scales that look something like this, and you could potentially confuse this one with other members of the genus, but probably not with anything outside Dryopteris. One helpful thing with Dryopteris is to look for persistent green fronds from last year... D. marginalis can sometimes have them, which would also help get this to species.
Ostrich fern, Matteuccia struthiopteris, is a good fern to be able to identify in fiddlehead stage, since it's the only fern whose fiddleheads are considered safe to eat. This one is easy to identify because of the deep groove which runs down the front of the stipe (you can see it here), and also because of the very smooth look of the stipe, which you can see in the photo below. They can sometimes have a fairly dense covering of golden scales, but they seem to outgrow them quickly, unlike the Dryopteris, above, which hangs onto the scales for a long time as it grows.
Maidenhair fern, Adiantum pedatum, often has reddish to purple stipes, which make it easy to identify, as do the white hairs that frequently occur along the base of the stipe. The ones pictured here also have some scales in addition to the hairs, but the reddish coloration is the real giveaway that this is Maidenhair: