Attract beneficial Mason bees to your yard for help in pollinating your flowers and vegetables. Mason bees will lay eggs in the tubes of the mason bee shelters, packing mud between each egg, laying the female eggs first followed by the male eggs ensuring that the males are mature by the time the females emerge and are ready to mate. Because Mason bees are not colonizing bees, they don’t live in a hive and don’t have a queen to protect and therefore are not aggressive. A delight to watch and at the same time helping nature!