Saururus cernuus; Saururuaceae (lizard tail family)
From the towpath I looked into the deep shade of a barely-dry vernal pond and saw hundreds of white plumes floating above a mass of green:
I figured it was lizard’s tail, but wanted to get a closer look (and some pics, natch), so I scrambled down a loose rock slide (very careful not to trod on any plants), thinking something like “this is probably great snake habitat”. Got some pics – even at ISO 6400 many were still woefully underexposed – and started to scramble back up the rocks. Heard a rustle. No big deal, hear that all the time. Had a look. Two very thick coils of black. Was getting the camera up when the thing hissed at me.
Pretty sure it was an eastern hog-nosed snake, but honestly I didn’t stick around long enough to get a better look. No pictures, either. If only I’d known that it likes to hiss and play dead, without biting… oh well.