Cedar bee house. Leaf cutter and mason bees are interesting solitary bees. They are used to polinate. They belong to the family Megachilidae and they nest inside cavities and build their egg cells with pieces of leaves.
They build multiple egg chambers per nest hole and in every one of them they deposit an egg with a little bit of pollen nectar and saliva for further development of the larvae. They do not compete with honey bees but they are also a very helpful friend to farmers since they are efficient pollinators.