Latex-producing-gall
Guides
Antistrophus silphii
Apical Rosinweed Gall Wasp
Antistrophus silphii is a gall-forming cynipid wasp native to North American prairies. The species induces stem galls on rosinweed (Silphium integrifolium), a tall prairie forb. Galls are large, solid, and succulent when young, becoming harder with age. The wasp has a single generation per year, with adults emerging in early summer.