This roadside plant was blooming in early November of 2012 in the Charleston area near both woods and marshland. Is it some sort of Pluchea?
If you recognize the low-growing plant surrounding with yellowish flowers or bracts, that would be a nice lagniappe. My best guess is a Milkwort (Polygala sp.), but could be way off-target.
you are correct – the pink flowered plant is a Pluchea, namely, Pluchea camphorata, Camphorweed. A related species is Pluchea purpurascens from the brackish marshes of the outer coastal plain. The only yellow flowered plant I see in your picture with the narrow grass-like leaves is Euthamia caroliniana, one of the grass-leaved goldenrods.
Dr, Steven Hill, Botanist, SCNPS