a green, fleshy, stem gall on white snakeroot

Asphondylia eupatorii Felt is a bivoltine species which produces a polythalamous, apical gall in the stem apex of Ageratina altissima (Linnaeus) in late July and August. The spring crown gall occurs on the same host in late May to early June.

"Gall succulent, just before terminal leaves"

"Galls appear in late summer and are 8-15mm long and 5-10mm in diameter, usually green, often elongate-tapered but sometimes globular, and polythalamous."

"Distr: New York and Maryland"