Gnats: Facts, Identification & Control

Gnat is the common name for many small, winged insects in the fly family.
Regionally, they are also sometimes called flies, midges & no-see-ums.

Contrary to popular belief, these tiny flying insects are not "babies", they are adults.
The tiny flying insects that many people call "gnats" could really be fruit flies or fungus gnats.
Depending on species, gnats can be biting or non-biting & will feed on plants, other insects or blood.
Males assemble in large mating swarms known as ghosts.
These swarms occur most commonly at dusk in large fields & above streets.
Depending on the species, gnat eggs are laid on land or water.
Larvae may be immobile or capable of movement by way of rocks & water plants.
Adults range in size from one to three millimeters.
The larval & adult stages of the gnat are considered both beneficial & detrimental.
Some species are excellent plant pollinators & feed on crop pests such as aphids & scales.
Other gnats, such as the Hessian fly, are crop pests, themselves.
Females of some species, such as the black gnat or black fly, feed on blood.
These gnats have been known to carry parasites & spread diseases to humans & livestock.
Due to the spread of river blindness & other health concerns, numerous programs have been established throughout the world to control gnat populations.

Gnat Problems:

While the small size of the gnat can make it appear less serious as a pest, it is important to remember that gnats reproduce quickly & populate infested areas in swarms.
This is how gnats become larger problems to homeowners or apartment residents.
Many gnat species are capable of being a pest & causing damage to the material where it lays its eggs.
Most damage caused by these "gnats "occurs during the larval stage, when they are feeding.
Fungus Gnats in House Plants: Fungus gnats lay their eggs in damp soil of plants that have been over-watered.
When the eggs hatch, the immature gnats feed on decomposing, organic material in the soil.
These gnats are attracted to fungus that grows in the soil of houseplants that have been over-watered.
Leaves, stems & roots are commonly affected in areas infested by these gnats.
Gnats feed on the roots & root hairs of plants, as well.
They are most harmful to small plants, but can also destroy large plants if the plant is already unhealthy or if the gnat population is extremely large.
Growers go to great lengths to prevent & eliminate gnat populations, as the damage caused by a gnat infestation can damage both ornamental & edible plants.
Fruit flies lay their eggs in fruit that is over-ripe or fermenting.
They tend to hover near fruit as they are attracted to the scent & moisture of decaying, organic material.
Fruit fly females lay their eggs in the fermenting fruit.
The larvae eat the fruit when they hatch. People can become ill from eating fruit that contains fruit fly eggs or larvae.

Gnat Control:

The best control for many gnats, such as fungus gnats, is to identify any plants that have wet soil & let that soil dry completely before the next watering.
This will kill the larval stages in the soil.
The adult gnats can be removed with a vacuum cleaner from windows & from around the plants.
For some gnat populations, their food source must be located & corrected.
Fruit should not be exposed to open air.
Keeping fruit in the refrigerator protects it from gnats & also prolongs the fruit's period of ripeness.
Watering plants only when they need water will help prevent fungus gnat infestations.
Schedule a pest control inspection if you are encountering difficulty ridding your home of these pests.

Some Other Ways to Get Rid of Gnats:

If you are already experiencing an infestation, there are several commercial products that may assist in controlling their populations.
Most traditionally, people use fly swatters to kill individual insects.
A number of pesticides & sprays can be used indoors.
However, these methods require positive identification of insects, which is best conducted with the assistance of a pest control professional.
Pesticides also require careful application, as they can prove harmful to humans & pets.
Electronic devices that electrocute individual gnats may help to control their populations outside.
Inside, insect traps that are plugged into electrical outlets work by emitting ultraviolet light sources.
Flying insects are attracted to this light & are caught by the sticky surface of the trap when they approach.
Most of these methods address only individual, adult specimens.
In order to properly treat an entire gnat infestation, including larvae, it is best to consult a pest control professional.