Biology:
The common house fly is a pest all over the world. The adult has the fourth wing vein sharply angled and four length-wise dark stripes on the top of the thorax. Its face has two velvety stripes which are silver above and gold below. Each adult female begins laying eggs a few days after hatching, laying a total of five to six batches of 75 to 100 small, white oval eggs. In warm weather these hatch in 12 to 24 hours into cream-colored larvae which burrow into the food material on which they hatched. These larvae grow and pupate in 4 to 7 days in warm weather. The mature larva contracts until its skin forms a case about 1/4 inch long. Inside this case, the true pupa forms.When fully formed, the adult fly breaks open the end of the pupal case and emerges. It is ready to mate within in a few hours after merging. The hardened larval skin which is left behind still exhibits most of the characteristics which are used in larval identification; thus determination can often be made on the basis of the skin alone.

During warm weather two or more generations may be completed in a month. Normally the population builds up and is greatest in early fall months. The method of over wintering is not well understood, but in some areas populations develop indoors throughout the winter. House fly eggs are laid in almost any warm moist material which will furnish suitable food for the growing larvae. Animal manure, human excrement, garbage, decaying vegetable material and ground contaminated with such organic mater are suitable materials.

Although they are attracted to a wide variety of food materials, house flies have mouthparts which enable them to ingest only liquid materials. Solid materials are liquefied by means of regurgitated saliva. This liquefied food is then drawn up by the mouthparts and passed onto the digestive tract.

During daylight hours house flies will rest on floors, walls and ceilings indoors. Outdoors they will rest on plants, on the ground, on fence wires, garbage cans and other similar surfaces. At night they will rest principally on ceilings, electric wires and dangling light cords indoors. In all situations they prefer corners and edges or thin objects such as wires and strings. Night resting places are usually near daytime sources of food and are usually 5 to 15 feet off the ground.
 

Recommended Control Measures

Exclusion and Sanitation, Insecticides, Traps, and Aerosols

1. Exclusion and Sanitation:

• Sanitation is the first measure of defense, even though there are various traps and sprays that are used to kill flies, it is necessary to eliminate the source in order to eliminate them
• Whenever possible, food and materials on which the flies can lay their eggs must be removed, destroyed, as a breeding medium, or isolated from the egg-laying adult. Killing adult flies will reduce infestation, but elimination of breeding areas is necessary for good management.
• The key to controlling these infestations is to locate and eliminate their breeding sources.