Artificial Nesting Sites for the Propagation of the Leaf-Cutter Bee, Megachile (Eutricharaea) rotundata, for Alfalfa Pollination

Abstract

The leaf-cutter bee, Megachile rotundata, although endemic to Eurasia, is found throughout most of continental United States where it has been reported polylectic on a variety of floral hosts. In the Pacific Northwest it is oligolectic on alfalfa, taking both pollen and leaf-cuttings from that plant. The bee does not excavate its own holes, but rather accepts any burrow or partially protected excavation that approximates its size. The paper reports that the bee accepted holes bored in timbers and milk straws set in tin containers without any apparent discrimination. Such stocked containers are readily amenable to manipulation and storage. This flexibility would permit the grower to relocate stocked timbers and straws throughout the field each spring, thus insuring adequate pollination of his crop by this bee species.