"Mature galls range from vertically symmetrical to pear-shaped, with irregularities in shape being more pronounced than in [G. gallaesolidaginis, G. jocelynae, G. salinaris]."

"The opening of the adult exit to the outside is located in the upper one-third of the gall, sometimes in the narrow part of pear-shaped galls... [This species] does not make a bung; only intact plant epidermis caps the finished adult exit. This cap is usually less visible externally than those the other other gallers fusing caps of intact plant tissue, and thus may be thicker. The cap has a single layer of silk on its inner side ... Exit caps are translucent when the exit sides of bisected galls are held up to a lamp. The pointed adult frons is probably adapted for penetrating a thick exit cap."

"...reared adults and galls of [this species] came from Aster novae-angliae, A. pilosus, A. simplex, and A. praealtus. The foodplant reported by Fyles (1911b), Aster junceus Ait., is now referable to A. junciformis Rydb." [in 2022, POWO lists this as a synonym for Symphyotrichum boreale".]