No-See-Ums

What’s biting you? Coping with No-See-Ums

During the summer months many of us have to cope with no-see-ums. They are small biting flies that are barely visible to the naked eye, but their bites can be very painful and annoying. They are also known as biting midges or punkies. Some mistake their bites as flea bites or chiggers. For us that spend a lot of time in our gardens, no-see-um(s) bites can be a daily occurrence.

The no-see-um species found in Arizona and the southwest are of the genus Culicoides (family Ceratopogonidae). Adults are less than 1/16-inch long which means they can easily pass through normal window screens. They are most active in early mornings and evenings of mid to late summer. So August is prime time for these little pests. Mouth parts are well developed with elongated mandibles adapted for blood sucking. Both males and females feed on flower nectar but only the female feeds on blood. She must consume blood for her eggs to mature and become viable.

No-see-um eggs are laid on moist soil. Common breeding areas include the edges of springs, streams and ponds, muddy and swampy areas, tree holes, and even water associated with air conditioning units. University of Arizona Entomologist, Carl Olson, says they also breed in moist disturbed soil such as that found around construction sites or freshly plowed ground. The eggs hatch in as little as 3 days. The worm like larvae have short brush like breathing structures that allows them to breathe in an aquatic environment. Although larvae are not strictly aquatic or terrestrial, they can not develop without moisture. After feeding on decomposing organic matter and pupating, adults emerge, feed, and mate.

Bites of these tiny flies are painful and irritating. The bite usually starts as a small red welt or water-filled blister that itches. Once scratched, the welt can break open and bleed, but the itching usually continues. The best strategy to prevent no-see-um bites is to wear long sleeve shirts, long pants, shoes and socks, and a hat during times when no-see-ums are most active. While sometimes mistaken for a mosquito, No-see-ums do not spread West Nile virus. However, their bite can be painful and precautions should be taken.

So enjoy the last few weeks of summer gardening, and take precautions to avoid the No-See-Ums.