Sanguisorba canadensis; Rosaceae (rose family)
First, an apology – the picture above is a little misleading. The green branches behind the inflorescences are balsam fir, which makes for a poor photo illustration. Sometimes I don’t have much of a choice, though.
The presence of balsam fir should be a clue that once again, I’m cheating. I found this plant in Nova Scotia, and didn’t pause long enough for a proper photo shoot. Here’s a look at the leaves:
Canadian Burnet is native to the eastern US and Canada and the Pacific Northwest. Though it does occur in Maryland, it is probably not a plant of the Potomac gorge; I’ve found references to it growing in Baltimore County and in the Blue Ridge, and west of there. Sadly it is either threatened or endangered in nine states, including Maryland.
Burnet is a perennial that likes a wet habitat, though it is fairly drought resistant. It will grow up to five feet tall. Four other species (three native, one alien) of Sanguisorba are found in North America.
In the past burnet sap was used to staunch wounds. The genus name comes from Latin words meaning “blood” and “to suck in” (presumably that’s also the root of the word “absorb”).