Osmia is the genus of mason bees—but what does the name signify? “Osmia” means “odor” in ancient Greek, and in this case, it refers to the lemony scent used by female masons to mark their own nests for unmistakable identification.

There are 130 species of Osmia native to North America and more than 300 worldwide. They are not in the same family as is the honey bee (Apidae); rather, they belong to Megachilidae (“large-lipped bees”), and therefore more closely related to the leaf-cutter bees that are in the same family.