Two types of small flies occasionally appear in kitchen areas. Several species of fruit flies (also known as pomace or vinegar flies) are common in kitchens. They are from 1/16-1/8 inch (1-3mm) long, yellowish or brownish with black markings, and fairly bristly. The larvae (maggots) develop in decaying vegetable matter, feeding on the yeast and molds which grow on over-ripe fruit or vegetables. In the home they are found near decaying potatoes, fruits and vegetables, flower bulbs, bread and baked goods containing yeast, beverages (beer, pop and fruit juices), and vinegar. They are also occasionally found in the small quantities of milk, catsup, juice or pop left in empty bottles and in sour dishcloths and mops. Disposal of infested items is generally sufficient to eliminate them. A pyrethrin spray is all that is required to eliminate the adults. A trap can be made from a Mason jar fitted with a paper funnel. Bits of banana sprinkled with yeast make a good bait that will last about two weeks. Check the trap periodically for larvae. The larvae in the trap can be killed with hot tap water (over 150 degrees F.).

A second type of small fly that is frequently encountered in the kitchen area is the moth (drain) fly. These flies are 4-5mm (1/16-1/4 inch) long, grayish, densely hairy and hold their oval wings rooflike over the abdomen. Their flight is weak but they are very agile runners. The larvae of these flies develop in sink traps and other stagnant water. Thus they are common in laundry tub and basement floor drains, sumps, toilet and shower drains, as well as the kitchen sink (especially if there is a garbage disposal). The larvae feed on sewage and other organic matter that builds up on the inside of drain pipes.

To kill the larvae, scrub the organic matter from the drain pipe (especially the trap) and then rinse with boiling water. A pyrethrin spray may be used to kill the adult flies, if needed. DO NOT put any insecticide into drains.

For a complete listing of suggested control options for all home, yard and garden insect pests contact your local Extension Service, found under local government in the phone book.

Read and follow instructions on the pesticide label. Heed all warnings. Check with your physician if you have any concerns regarding your personal health risk.

Gary A. Dunn, M.S., R.P.E. Extension Entomology Specialist



MSU 2003