Monday, August 4, 2014

Tiny Flies in the Kitchen

Is the kitchen invaded with tiny flies hovering over a fruit bowl? Are you thinking that fruitflies have come in from the orchard? In all probability these are not fruit flies, but rather, what are commonly known as vinegar flies or drosopila, in the insect family, Drosophilidae.

 Unlike the fruitflies which cause major damage to fruit and vegetables, the vinegar flies are found in association with overripe fruits and vegetables. They do not cause the fruit to rot but are actually attracted to rotting and fermenting food. The larvae feed principally on the yeast in the fermenting fluids. Drosophila flies have been widely used by geneticists around the world in studying the laws of heredity. This is because they are prolific, have a short life cycle and are easy to rear.

Vinegar flies do not bite humans but are strictly a nuisance pest. For control, it is best to concentrate on eliminating the larval feeding sites and the breeding areas. Sanitation is critical. By eliminating overripe fruit sitting on the counter and exposed kitchen garbage, these pests can be controlled. All exposed fruits and vegetables should be refrigerated. Pyrethrin insecticides, organic and non-organic types, are effective in killing vinegar flies, but only when contact is made. 

A Nontoxic Way of Managing Vinegar Flies
From Ohio State University comes this simple trap. Take a Mason or similar jar and cover or paint the outside top third of the jar. Coat the inside of the jar with a sticky liquid such as diluted honey or vegetable oil. Invert the jar over bait such as crushed bananas. Rest the jar upside down on two blocks of wood to allow flies space enough to feed on the bait. After the flies leave the bait, they will fly upward to the light portion of the jar and get stuck on the sides when they rest.