Eric Mader, Pollinator Outreach Coordinator, the Xerces Society for Invertebrate Conservation 

The alfalfa leafcutter bee (Megachile rotundata) pollinating alfalfa.
Figure 7.1 The alfalfa leafcutter bee (Megachile rotundata) pollinating alfalfa. Photo by Theresa Pitts-Singer.

The alfalfa leafcutter bee (Megachile rotundata) (Figure 7.1) is the second oldest managed bee species in US. Like the honey bee, the alfalfa leafcutter bee (sometimes called the alfalfa leafcutting bee) is a nonnative species introduced from Europe and the Middle East. There are various explanations for the bee’s introduction in the US. One common theory is that the bees accidentally arrived inside wooden shipping crates imported from the Mediterranean region. The earliest record of the alfalfa leafcutter bee in the US dates from 1937 in Washington, DC.