Photo by Owen Strickland on iNaturalist · CC BY 4.0 · specimen identified as Osmia lignaria lignaria
PollinatorActive Mar–Jun
Mason bee
Osmia spp.
- When
- Mar–Jun — March, April, May, June. Earlier in the south, later in the north.
- Where to look
- Early fruit blossom. Nests in hollow stems and drilled blocks, sealing cells with mud.
- How to know it
- Small, dark metallic blue-black, carrying pollen dry on the underside of the abdomen rather than on the legs.
- What it does for you
- One mason bee does the pollination work of a hundred honey bees on apples. Solitary, docile, and easy to house.
Found in these regions
- Boreal North & Taiga
- Boreal Forest & Shield
- Acadian Forest & Atlantic Coast
- Great Lakes & St. Lawrence Lowlands
- Northeast Atlantic Coast & Piedmont
- Appalachian Highlands
- Central Hardwoods & Interior Plateaus
- Southeastern Piedmont & Coastal Plain
- Gulf Coast & Mississippi Lowlands
- Florida Peninsula
- Prairies & Great Plains
- Western Mountains & Interior Plateaus
- Pacific Maritime
- Mediterranean California
- Deserts & Dry Basins
- Hawaiʻi & the Tropics
Is it active near you?
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Also active in September
PollinatorMay–OctMonarch butterfly
Danaus plexippus
Orange with heavy black veins and a white-spotted black border. The caterpillar is banded yellow, white and black.
What it does in the garden →Photo: Christine Young · CC BY 4.0
PollinatorMay–SepRuby-throated hummingbird
Archilochus colubris
Tiny, iridescent green above; the male has a black-looking throat that flares ruby in the right light.
What it does in the garden →
BeneficialJul–OctPraying mantis
Mantidae
Long green or brown body, triangular head that swivels, and folded raptorial front legs.
What it does in the garden →