by Nanette Londeree, Master Rosarian
SIGNS
Moderate-sized (less than ¼ inch to nearly one inch long) stout-bodied, black bees with light bands across the abdomen and a covering of pale hairs on the underside
Adult insects that resemble honey bees
A bee where the abdomen appears light yellow to deep gold in color (when carrying pollen)
Individual bee nests in soil, holes in wood, in plant stems, empty snail shells
SYMPTOMS
Semicircular holes in the margins of leaves or blossoms of roses
Neatly cut ¼ to ½ inch circles in leaves of azaleas, ash, redbud, bougainvillea and other plants with thin smooth leaves
CAUSE
Leafcutting bees – Megachile spp
OPTIMAL CONDITIONS / HABITAT
Solitary bees; they do not live in large groups or colonies like honey bees
Important native pollinators of many wildflowers; they also pollinate fruits and vegetables and are used as pollinators by commercial growers of blueberries, onions, carrots and alfalfa
Hollow twigs and other natural cavities, holes in buildings and occasionally in the ground for nestingOverwinter in nests as newly formed adults
TREATMENT
Prevention:
None
Elimination:
None – bees are important pollinators and should not be killed
No effective nonchemical controls are known
GOOD GUY / BAD GUY?
Can be a nuisance by destroying the aesthetics of a plant; rarely harms the plant
A good guy as an active pollinator