Blue orchard mason bees (Osmia lignaria) are a native species to the west coast of Canada and the United States. They are solitary bees meaning that they live as individuals, and are most well known for their pollination services that they provide to fruit trees and berry plants in the early to mid-spring. While also pollinating a variety of other food crops, orchard mason bees forage earlier in the morning and later in the afternoon, and are seen flying at lower temperatures than their cousins the honeybees. In fact, just 250-300 female blue orchard mason bees are needed to pollinate an acre of apple trees.
Typically, blue orchard mason bees inhabit wooded areas and are often in and around wood homes and structures. They are most commonly seen inspecting and entering between shake house siding, nail holes, and other wood cavities during March to June. However, homeowners should not be concerned with mason bees since they do not excavate holes in wood and are not destructive insects. Moreover, they are non-aggressive and will only sting if handled roughly or if they are trapped under a person’s clothing.
Blue orchard mason bees can be identified by their shiny dark blue color, and are slightly smaller than a honey bee. Female mason bees can be differentiated from the males by their larger size of body and shorter length of antennae. Since they are solitary bees, the female is tasked with establishing a nesting site, collecting sufficient food supply from available forage, as well as laying one to two eggs each day during the 6 to 8 weeks that she is active.
Creating Blue Orchard Mason Bee Habitat
As a native pollinating species on Vancouver Island and in the Pacific Northwest, and their gentle characteristics make the blue orchard mason bee ideal for enhancing populations through the building and placement of nests around homes and other structures near forage sites. It is desirable to protect the nests from strong winds and rain and positioning the nests where they will receive morning sunlight. Blue orchard mason bees like to be near a natural water source where there is a good supply of mud for nest construction and plant a variety of wild flowers and fruit trees on which they like to forage. Blue orchard mason bee favourites include most fruit trees, especially cherry, plum, and apple as well as berry bushes, dandelions, and Oregon grape.