Illustration of Ageratina altissima var. altissima from Flora of North America

Illustration of Ageratina altissima var. altissima from Flora of North America
Photographer: Taken from Nesom, Guy L. “Ageratina” in Flora of North America, Vol. 21, p. 549. Oxford University Press, Inc...

Full citation below:

Nesom, Guy L. “Ageratina” in Flora of North America, Vol. 21, p. 549. Oxford University Press, Inc.  New York, NY.  2006.