Below ground nest boxes used by five species of bumblebee Bombus spp. near Urbana, Illinios, USA
Frison T.H. (1926) Experiments in attracting queen bumblebees to artificial domiciles. Journal of Economic Entomology, 19, 149-155.
Some bumblebee species, including the American bumblebee Bombus pensylvanicus, are thought to be declining in North America. This study tested the uptake of metal or wooden underground bumblebee nest boxes in the vicinity of the city of Urbana, Illinois, east-central USA.
Nest boxes were buried with the top of the spout at ground level, in woods or meadow lands at University Woods, Brownfield Woods and Whiteheath, in April of 1915, 1916, 1917 and 1919. Each nest box was supplied with dry grass from a field mouse nest. In latter years, wooden and metal bucket nest boxes had the bottom removed and replaced with fine copper gauze, to allow drainage, and were given removable inner lids made of red glass, to allow observation of the bees without disturbance.
17 of the 36 nest boxes (48%) were occupied, by five different bumblebee species - the black and gold bumblebee Bombus auricomus, the American bumblebee B. pensylvanicus ( synonym americanorum), the two-spotted bumblebee B.bimaculatus, the brown-belted bumblebee B.griseocollis (synonym B.separatus)and the common eastern bumblebee B.impatiens.