What Are Shore Flies?
Shore flies are tiny insects that can become a nuisance in greenhouses and other areas with excess water. They resemble fruit flies, but they have distinctive dark wings with five light spots on each one. Shore flies are attracted to algae, which they feed on.
Are Shore Flies Harmful to Crops?
Unlike fungus gnats, which feed on plant roots, shore flies do not directly damage crops. However, they can be a nuisance and may transmit root disease organisms. Additionally, heavy infestations can leave unsightly black “fly specks” on leaves.
How to Prevent Shore Fly Infestation
- Limit algae growth: Use less fertilizer and avoid overwatering.
- Repair leaks: Prevent standing water by fixing any leaks in hoses or irrigation systems.
- Clean surfaces: Regularly remove algae from greenhouse walls, floors, gutters, and benches.
How to Get Rid of Shore Flies
Natural Methods:
- Insecticides: Many insecticides can eliminate shore fly larvae but not adults.
- Adulticides and larvicides: For well-established populations, use both an adulticide to kill adults and a larvicide to target larvae.
Cultural Methods:
- Traps: Place sticky traps near areas where shore flies congregate.
- Vacuuming: Vacuum up shore flies and larvae regularly.
- Beneficial insects: Introduce predatory insects, such as ladybugs or lacewings, to feed on shore flies.
What’s the Difference Between Shore Flies and Fungus Gnats?
Both shore flies and fungus gnats are common greenhouse pests, but they have key differences:
- Appearance: Shore flies have dark wings with light spots, while fungus gnats have clear wings.
- Diet: Shore flies feed on algae, while fungus gnats feed on plant roots.
- Damage: Shore flies can transmit root disease and leave unsightly marks on leaves, while fungus gnats can cause significant damage to plant roots.
Other Frequently Asked Questions
What Does Shore Fly Damage Look Like?
Heavy shore fly infestations can leave black “fly specks” on leaves, which are unsightly but generally harmless.
Can Insecticides Harm Adult Shore Flies?
Yes, some insecticides can kill adult shore flies. However, it’s important to use both an adulticide and a larvicide for effective control.
What is the Best Way to Control Shore Fly Larvae?
Vacuuming up larvae and using larvicides are effective methods of controlling shore fly larvae.
How to Clean Algae Off Greenhouse Surfaces to Deter Shore Flies?
Use a steam cleaner or manually scrub algae off walls, floors, gutters, and benches to reduce shore fly attraction.
Is Shore Fly Infestation an Aesthetic or Practical Concern?
Shore fly infestation is primarily an aesthetic concern, as they do not directly damage crops. However, they can transmit root disease organisms and be a general nuisance.
Does Shore Fly Larvae Feed on Plant Roots?
No, shore fly larvae do not feed on plant roots. They feed exclusively on algae.
