There are a wide variety of insects that invade and destroy lawns. Most lawn insects live and feed near the roots of the grass, but others live near the grass blades. An abundance of flying insects in and around the surface of the lawn are most likely frit flies. Flying insects living in a lawn are most easily killed using the proper insecticide application. Treating flying insects must be done as soon as possible to prevent eggs from hatching and increasing the population.
Purchase a liquid insecticide that is labeled for use with frit flies or other flying insects. Insecticide packaging usually contains a long list of insects that the product can eliminate.
Wait until a day when there is no rain predicted and when there is little to no wind.
Spray the surface of the the lawn with the insecticide as directed by the manufacturer's instructions. Some insecticides come equipped with a sprayer, but others must be mixed with water inside of a larger garden sprayer.
Wait three to four days and examine the lawn for live flying insects. If there are any live insects, repeat the insecticide application.