Six Osmia simillima females used communal nest entrances to gain access to their nests in a piece of buried wood. Some nest characteristics are described.
"Use of Communal Nest Entrances by Osmia Simillima (Hymenoptera: Megachilidae),"
The Great Lakes Entomologist, vol 26
Available at: https://scholar.valpo.edu/tgle/vol26/iss1/10