Well, I was just proud as can be to guess Joe-Pye Weed for this plant that is taller than I am, in one of the Nelson Park community garden plots, and then to remember the name Eupatorium, but alas, as has been mentioned a few times on these forums, that has been renamed to Eutrochium. Well, not all of them. Eupatorium still has the white-flowered ones with mostly opposite leaves, see Wikipedia Eutrochium - Wikipedia. I found a comparative study of Joe Pye Weeds at https://www.chicagobotanic.org/downloads/planteval_notes/no37_joepyeweed.pdf. Only the Eutrochium seem to look like this. Eutrochium fistulosum - Hollow Joe-Pye Weed has a kind-of give-away in the name, and someone was kind enough to have broken off a large stem and cut off another stem. Both hollow. Then I found another site, Eutrochium fistulosum (hollow Joe-Pye weed): Go Botany, that says this is not necessarily a distinguishing feature, as E. maculatum can have hollow stems. Well, dang! That species, though, has spotted stems and three or four leaves in the whorls (sometimes more). This plant had no green stems and from four to seven leaves in the whorls. Many leaves were 20-27cm long, and the flower heads were much larger than that. The stems here definitely did not look like the stem in this E. maculata photo: Photo of the stem, scape, stalk or bark of Spotted Joe Pye Weed (Eutrochium maculatum) posted by nativeplantlover - Garden.org
