We may be experiencing a drought, but don't let that fool you into thinking there's no reason to worry about mosquitoes - they're still a menace to the community.
Mosquitoes are more than just an irritating annoyance. They can spread numerous diseases. In tropical regions of the world, they are vectors for malaria, yellow fever, dengue fever and several other diseases. In the Southeastern United States, West Nile Virus is the primary disease spread by mosquitoes.
Luckily, a few simple actions can help reduce the nuisance effects of mosquitoes.
Mosquitoes need to have a source of water in order to reproduce. Sources of water include natural bodies of water - creeks, rivers and lakes - and man-made sources, like old tires, containers left outdoors and gutters on homes.
The female lays her eggs in the water, and the larvae (immature forms of the mosquitoes) hatch. They appear as small "wigglers," maybe 1⁄8 to 1⁄4 inch in length. They have siphon tubes for breathing and hang upside down from the water's surface. They undergo pupation and emerge from the water as adult, flying mosquitoes.
Only the females bite humans and other animals to suck blood, and they do it to obtain the proteins necessary for laying eggs. The mosquitoes secrete saliva to keep the wound from clotting. Most people are allergic to the saliva, which is what causes those itchy welts.
Several steps can be taken to reduce mosquitoes around your home. The best course of action is to remove their breeding sites as much as possible. Begin by cleaning out your gutters and search for any containers and other items that may have standing water - especially old tires - and dump them.
Ornamental water gardens and ponds can be treated with a "larvicide," a tablet that has chemicals targeting the mosquito larvae. Larvicide is sold under brand names such as Mosquito Dunks. The doughnut-shaped dunks will slowly dissolve and help control developing larvae for up to a month. It's harmless to fish, wildlife and pets.
Adult mosquitoes can be controlled by several methods. Apply insect repellents containing a chemical called DEET when outside or in high-risk areas. Wear light-colored, protective clothing - long pants, long-sleeve shirts, shoes and socks - when you'll be in an area with high mosquito populations. Also, keep screened doors and windows in good repair.
Chemical mosquito control should be used only as a supplement to getting rid of breeding sites. Pyrethrin aerosol sprays are effective in treating mosquitoes in the house, but they disperse rapidly outside, limiting their effectiveness.
Residual insecticides (malathion, permethrin) can be applied to shrubbery, ground covers and underbrush, and other places where mosquitoes rest during the heat of the day.
Burning mosquito coils can offer relief from the insects, but only in the immediate area. Follow all label directions and safety precautions when using chemical insecticides.
Timothy Daly is an agricultural and natural resource agent with the Gwinnett County Extension Service. He can be reached at 678-377-4010 or timothy.daly@gwinnettcounty.