Mining Bees
Andrena spp.
Andrenidae · Genus Andrena
The first bees on the wing each year. Mining bees are solitary ground-nesters that emerge in March and April — often while the ground is still cold — to pollinate willow catkins, cherries, redbud, and spring ephemerals before most other bees are active.
How to spot one.
Small to medium (0.3–0.5 inch)
Fuzzy body, often dark with pale hair bands
Hairy hind legs carry loose pollen (not packed like bumble bees)
Females often have a distinctive 'facial fovea' — small hair-lined pits on the face
How it lives.
Solitary. Each female digs her own burrow in bare or sparsely vegetated soil — often in aggregations of dozens or hundreds of burrows, but every bee works independently. No colony, no queen, no defensive behavior. Do not mow over an emerging aggregation.
The spec sheet.
- Type
- Bee
- Active
- March – June
- Native to NJ
- Yes
- Conservation status
- stable
- Family
- Andrenidae · Genus Andrena
Notable species.
Species you’re most likely to see, plus any of conservation concern.
Willow Mining Bee
Andrena milwaukeensis
Spring specialist on willow catkins
Carlin's Mining Bee
Andrena carlini
Early emerger; pollinates cherries and spring ephemerals
Bloodroot specialist bees
Andrena spp.
Oligolectic species that visit only specific spring wildflowers
What it needs.
Plants this species visits, feeds on, or depends on. Names in hydrangea link to the plant’s Field Guide entry.
Primary pollinator
Primary pollinator
Nectar source
Willows (Salix)
Primary pollinator
Wild cherries
Primary pollinator
Ground-nesting bees are threatened by two things gardeners do reflexively: heavy mulching (which blocks nest sites) and neonicotinoid soil drenches (which stay in soil for years). Leave bare soil somewhere on your property; skip the soil drench.
Xerces Society · Cornell Pollinator Network · Rutgers NJAES
Others in this group.
- BsBeeNative · NJ
Bumble Bees
Bombus spp.
Big, fuzzy, striped, social bees — the ones everyone recognizes. Bumble bees are the most efficient pollinators in New Jersey and the only bees here t…
- OsBeeNative · NJ
Mason Bees
Osmia spp.
Small metallic blue-black solitary bees that pollinate spring fruit trees more efficiently than any other insect on the continent. One female mason be…
- H&BeeNative · NJ
Sweat Bees
Halictus & Lasioglossum spp.
The smallest native bees in New Jersey — often under half an inch — and among the most abundant. Named for their attraction to human perspiration (a s…