Osmia lignaria

Osmia lignaria, commonly known as the orchard mason bee or blue orchard bee, is a megachilid bee that makes nests in reeds and natural holes, creating individual cells for their brood that are separated by mud dividers. Unlike carpenter bees, they cannot drill holes in wood. O. lignaria is a common species used for early spring fruit bloom in Canada and the United States, though a number of other Osmia species are cultured for use in pollination.

Native origin

O. lignaria is among 4000 native bee species of North America, and its species is divided by the Rocky Mountains into two subspecies, O. l. propinqua and O. l. lignaria. For those who keep mason bees, USDA entomologists have strongly suggested O. l. lignaria is kept because of its native origin, as the bees are likely to have greater success in their original climate and in propagation efforts.

Life cycle

Spring

The bees begin to emerge from their cocoons in the spring when the daytime temperature reaches 14 °C (57 °F). The males emerge first. They remain near the nesting site and wait for the females to begin their emergence, which can be several days to weeks depending on the number of days of warm weather. The first thing the females do is mate. A female will typically mate once, maybe twice. She will be absent from the nesting site for several days while she feeds and waits for her ovaries to fully mature.