This gall is formed at the intersection of the stem and the root. At this moment, it is uncertain whether the gall-forming insect is a Cecidomyid fly or a Cynipid wasp. These galls were "reared" over the winter and both a midge and a wasp species emerged, so it is possible that the wasp was parasitic on the fly. There is liitle information on the insects who make this type of gall, as the galls have been largely unknown.