Osmia lignaria

It is metallic dark blue, sometimes blue-green, and males have a distinct patch of white hair on the face.

Males are about two-thirds the size of a honey bee; females are larger.

The blue orchard bee is native to North America and occurs naturally across most of the United States.

Two subspecies have been described, an eastern and a western form, separated by the 100th meridian.

Unlike honey bees and bumble bees, it is solitary rather than social.

It produces only one generation a year.

It spends the winter as an adult inside its cocoon.

After emerging in spring, males and nesting females live only about 4 to 6 weeks.

In the wild, it usually nests in old beetle burrows in dead logs.

Females need a source of mud to build the walls between their nest cells.

It visits many wild plants but strongly prefers fruit tree flowers when they are available.

When flowers are plentiful, females tend to forage within about 100 m (300 feet) of their nests.

It forages and pollinates even under cloudy skies and at lower temperatures than most other bees.

As few as 250 nesting females per acre (625 per hectare) are enough to give the most pollination in apple orchards.