The Large Bulb Fly (Merodon equestris) is a hoverfly species whose larvae feed on the bulbs of ornamental plants. While the adult fly resembles a bumblebee and feeds on nectar, the larval stage can damage garden plants by burrowing into bulbs. Because of this dual lifestyle, bulb flies are both pollinators as adults and occasional garden pests during their larval stage.
Quick Facts
- Family: Syrphidae
- Habitat: Gardens, ornamental flower beds
- Diet (Larvae): Plant bulbs
- Status: Occasional garden pest
Identification
Adult bulb flies resemble bumble bees with fuzzy yellow and black bands. This mimicry helps protect them from predators. Adults are strong fliers and are commonly seen hovering near flowers.
The larvae are pale, maggot-like insects that develop inside plant bulbs.
Distribution
The large bulb fly is native to Europe but has spread to North America and other temperate regions through ornamental plant trade.
Life Cycle
Adult females lay eggs near plant bulbs. After hatching, larvae burrow into bulbs and feed on plant tissue before pupating in the soil.
Pest Status
Larval feeding can destroy bulbs of ornamental plants such as tulips, daffodils, and lilies.
Prevention
- Inspect bulbs before planting
- Remove damaged bulbs immediately
- Rotate planting areas in gardens
Control
Removing infested bulbs and maintaining healthy soil conditions are effective ways to limit infestations.