If you have fruit trees, berry bushes, or other garden products to pollinate, look to the mason bee! As honeybee populations are in decline, mason bees can help pick up the workload in your garden. Put one of these houses on a fence post or at the corner of a raised garden bed and wait for them to find and make a home in their new digs.
Bonus fun for the kids observing the bees as they make their homes and work your garden, and then hatch next spring to do it again! Mason bees attracted by these houses do not sting, nor do they create holes in the other wooden things you want left whole--no risk and all reward!
"Masons are solitary like most native bees. This means that each one tends to its own brood, instead of having a queen and worker bees. However, they seem to like the company of others of their kind and happily build their nests next to each other. They also readily accept the hollow tubes provided by the orchard grower for this purpose. This proves to be very beneficial to the fruit tree grower because it makes it easy to manage this valuable orchard helper.
Not only commercial fruit growers, but home gardeners too the opportunity to have some orchard bees in their own gardens by placing hand-made or store-bought bee houses or bee blocks in their yards."