The poplar gall Saperda, Saperda inornata Say, is a common pest of trembling aspen, Populus tremuloides Michx, in Michigan forests. Through its egg-laying activities and larval feeding, this insect causes wood defects and tree mortality (Graham et al., 1963). While studying natural populations of this insect (Grimble and Knight, 1970), we collected many galls and found through rearing and dissection that they harbor a large and varied insect fauna.
Grimble, David G.; Knight, Fred B.; and Nord, John C.
"Associated Insects Reared from Galls of Saperda Inornata (Coleoptera: Cerambycidae) on Trembling Aspen in Michigan,"
The Great Lakes Entomologist: Vol. 4
, Article 3.
Available at: http://scholar.valpo.edu/tgle/vol4/iss2/3