Helenium Species, Virginia Sneezeweed

Prefers limestone soils. Grows along stream embankments. According to Virginia Dept of Conservation, (...Read Moreov/natural_heritage/documents/fshelevirg.pdf" target="_dgnew"rel="nofollow">http://www.dcr.virginia.gov/natural_heritage/documents/fshel...),
it exclusively grows in Virginia, where it is endangered & illegal to harvest seed.

It bears a strong resemblance to Helenium autumnale, so without professional identification, I can NOT confirm that it was planted several years ago* in a designated conservation area that is an ideal habitat in PA & is thriving.

It's possible that the flowers at the conservation site are H. autumnale, but the seed heads do not resemble the photos of H. autumnale posted on DG. The amount of natural variation in H. autumnale would help with the I.D. of the plants I've seen in my travels.

* I have no affiliation with nor do I know anyone involved with this conservation site or its riparian buffer enhancements several years ago.