Blue Orchard Bee

Osmia lignaria

Classification

Pronunciation

How to pronounce Osmia lignaria: /ˈɔz.mi.ə lɪɡˈnɛə.rɪə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Images

Osmia lignaria propinqua by Harley Hosford. Used under a CC BY 4.0 license.
Osmia lignaria P1170470a by 
xpda. Used under a CC BY-SA 4.0 license.
Osmia lignaria Male by The Packer Lab. Used under a Attribution license.
Mason bee (Osmia lignaria) (26134020756) by Oregon State University. Used under a CC BY-SA 2.0 license.
Osmia lignaria P1170471a by 
xpda. Used under a CC BY-SA 4.0 license.
Osmia lignaria P1170469a by 
xpda. Used under a CC BY-SA 4.0 license.

Summary

Osmia lignaria, or the blue orchard bee, is a native North American bee known for nesting in holes and reeds, and is a vital pollinator for various fruit trees. They are univoltine, with adults emerging in spring, where they play a significant role in fruit bloom pollination.

Physical Characteristics

Female, 10-11 mm; Male, 9-10 mm; Metallic blue, almost black.

Identification Tips

Females are larger than males and can be distinguished by their nesting behaviors and size.

Habitat

Woodlands and forest edges; nests in natural holes and reeds.

Distribution

British Columbia to Quebec and the New England states, south to California, Oklahoma and Georgia. Native to the western US.

Diet

Visits flowers of cherry, pear, and apple as well as quince, laburnum spp, and blueberry.

Life Cycle

Univoltine; adults are active mostly from March to May; eggs develop by early summer into fifth instars. Cocoons are spun and dormancy begins, pupation occurs by late summer, and adult eclosion occurs a month later.

Reproduction

Females mate typically once or twice and lay one egg per mud-sealed partition in the nest. Eggs are fertilized for females and left unfertilized for males, laid in a ratio of about three males to one or two females per cavity.

Predators

Kleptoparasitic pollen mite (Chaetodactylus krombeini), sapygid wasps (genus Sapyga), cuckoo bees (Stelis montana), and several chalcidoid wasps.

Ecosystem Role

Important pollinator for early spring fruit bloom in orchards.

Economic Impact

Management and development for use as a pollinator in fruit orchards; contributes significantly to agricultural productivity.

Collecting Methods

  • Prepared nesting materials
  • Marketed bee condos

Preservation Methods

  • Cocoon storage for winter

Evolution

Divided by the Rocky Mountains into two subspecies: O. l. propinqua (western) and O. l. lignaria (eastern).

Misconceptions

O. lignaria is not aggressive and only stings if severely threatened; the stinger is primarily an egg guide.

Tags

  • pollinator
  • native species
  • bees
  • Osmia lignaria
  • agriculture