Galls comprise visibly swollen seedheads with deformed and clustered flowers. Internally, they are thick-walled, with 2-4 larval chambers each containing a small larva. The larval chambers are usually found inside the bracts. They possibly overwinter within the galls as they were found particularly late in season for most flower galls. The galls appear to be widespread in the Cincinnati, Ohio area in early October, and have been observed several times in the city.