Although the lawn is part of the home, it is also part of the outdoors and, as such, is home to a host of animals and other organisms that search grassy areas for food and water. Many of these animals are insects including flies that are small enough to take advantage of condensation on grass. Some of these insects are harmless to humans while others can be deadly.
The several species of small flies called frit flies are commonplace in a summer yard and are found both near the grass and hovering at up to eye level in small swarms. Gnats such as frit flies live by feeding on the blades of grass in a yard. These flies also breed on the grass blades, laying tiny off-white eggs that hatch small white maggots that bore into grass stems. While small, frit flies reproduce quickly and they can damage lawns severely over time if left untreated.
The big-eyed bug gets its name from large eyes that pop out of the sides of its head. This fly is slightly larger than the frit fly and sustains itself not by attacking the grass itself but by attacking other animals lurking in it. Big-eyed bugs look for other flies, caterpillars, mites and other small insects in the grass. These small insects are actually beneficial to have in your lawn, since they feed on insects that would otherwise be eating your grass.
One of the largest groups of lawn-inhabiting insects is the beetles. Species such as the Japanese beetle, May beetle, oriental beetle and the Asiatic garden beetle all look for small roots and tubers just under the grass. While beautiful to look at, many of these beetles are serious pests, undermining the grass by eating at its roots and feeding on particulate matter that would otherwise contribute to plant nutrients.
Species of aphids such as greenbugs can be detrimental to lawns. These insects are so small that as many as 30 of them can sustain themselves on a single blade of grass. The aphid injects the grass with a poison that kills part of the blade, allowing it to be ingested. As the aphids reproduce, brown patches of grass are noticeable on the lawn. Aphids are controlled by occasional sprays with insecticidal soap.
Perhaps one of the most dangerous insects to commonly infest a lawn, mosquitoes carry diseases such as malaria and West Nile virus. These parasitic animals will infest lawns that have stagnant pools of water such as a rain-filled bucket or even a drenched patch of thatching or dead leaves. Lawn treatments are available for eliminating mosquitoes that have established a presence in the lawn.