hyssopleaf thoroughwort (Eupatorium hyssopifolium)

Eupatorium hyssopifolium, also known as Hyssopleaf thoroughwort, is a fall-blooming herbaceous plant native to North America. Like other members of the genus Eupatorium it has inflorescences containing a large number of very small flower heads, each with 5 white disc florets but no ray florets. At 0.5 to one meter (20-40 inches) tall, it is towards the shorter end of the range of heights found in Eupatorium species.