Gnats are small two-winged insects that typically travel in large swarms. Black gnats include both biting and nonbiting forms and are found in nearly any place in the world where a river or stream is present. Biting black gnats lay their eggs in watery areas and require the blood of warm-blooded animals to survive. Gnats typically do not bite through clothing. With the proper attire, repellents and preparation, you can prevent black gnats from biting.
Increase air movement to keep biting gnats away. Set up fans, air conditioners or other sources of airflow where gnats are present.
Burn candles, torches or coils containing citronella or other biting gnat repellent. The smoke produced by these items will reduce bites.
Reduce vegetation in areas where biting black gnats thrive. Mow weedy areas, prune shrubs, and keep vegetation low to the ground to reduce gnats in the area.
Set up outdoor barriers near streams with running water. Black gnats lay their eggs in water. Dam the waterway with sandbags to create stagnant water in which the larvae cannot mature.
Clean up debris found in nearby waterways. Biting black gnats can attach to floating debris to grow and reproduce.
Place BTI cakes into the stream after damming the waterways. These doughnut-shaped cakes contain a larvicide that will kill off pests and prevent gnats that live in the watery areas from growing.
Apply an insect repellent containing 10 to 30 percent DEET. Always wear an insect repellent when outdoors, especially in areas where black gnats have infested.
Wear long sleeves, pants, gloves and a head net in areas where black flies are found in high numbers. Cover up as much skin as possible.
Set up a pyrethrum-based insect fogger to prevent the black gnats from biting. Insect foggers are only a temporary way to remove biting black gnats from an area.