The Blue orchard bee (Osmia lignaria) is one of the most interesting hymenoptera. Orchard bees are solitary, as most bees in Ohio are. They are extremely efficient pollinators and can be used by farmers to aid the honey bee (Apis mellifera) in pollinating orchard trees (hence the name). Even more interesting, they build “nests” in hollow tubes. The female orchard bees collect pollen that they form into nutrient packed balls. They then deposit a single egg onto the ball, and partition it into a segment of the tube using mud. They will repeat this over and over again until the tube is completely filled. When the egg hatches, the larva will feed on the pollen ball and eventually transform into an adult orchard bee.
Sources:
https://www.kqed.org/science/1928378/watch-this-bee-build-her-bee-jeweled-nest