They interfere with outdoor activities and can also be vectors for several diseases. Malaria, yellow fever and dengue fever are problems in other parts of the world. In our area, West Nile virus and encephalitis are troublesome although only a small number of individuals are affected each year. Mosquitoes cannot be totally eliminated from the property, but their populations can be reduced to where they are not as bothersome.
Any sources of standing water, such as natural bodies of water such as wetlands, ditches, lakes, or man-made sources such as old tires, containers left outside and gutters on homes will be attractive breeding sites for mosquitoes. Rapidly moving waters in creeks and rivers are not suitable breeding sites. The female mosquito lays her eggs in the standing water. The larvae, which are the immature forms of the mosquitoes, hatch and appear as small “wigglers” one-eighth to one quarter inch in length. The larvae pupate and then emerge from the water as adults. Only the females bite to suck blood to obtain the proteins necessary for their eggs. When it bites, the mosquitos' saliva that is injected into the skin causes the development of an itchy welt.
Even with the most prudent control measures, mosquitoes cannot be totally eradicated from a yard. However, steps can be taken to reduce the infestation of mosquitoes around your home. Most important, eliminate their breeding sites wherever possible. Clean out your gutters. Remove any containers and other items that may have standing water. Ornamental water gardens can be treated with a larvicide, which is a tablet containing bacteria that specifically targets the mosquito larvae. It is sold under various brand names such as Bactimos Briquettes, Mosquito Dunks and Mosquito Bits. The doughnut-shaped dunks will slowly dissolve and provide control for up to a month. When outdoors, apply insect repellants containing a chemical called DEET. Light colored protective clothing, long pants, shoes and socks should be worn in areas where mosquito populations are bothersome. Also, keep screened doors and windows in good repair to exclude them from homes.
Pesticides can be used as a supplement for mosquito control. Numerous application techniques are available. Since it is the most effective, the most commonly used one is an outdoor aerosol fogger. The use of pesticides should be done in the evening since mosquitoes are most active at this time. Residual insecticides, such as malathion and those containing permethrin can be applied to shrubbery, ground covers, underbrush, and other places where mosquitoes rest during the heat of the day. These applications will have to be repeated since relief is temporary due to the pesticides breaking down. When using pesticides, make sure you observe all label directions and safety precautions. Burning mosquito coils can give relief from the insects but only in the immediate area. Some of the products on sale for mosquito control are not always as effective as they claim. Mosquito plants, garlic, herbal remedies and ultrasonic devices are not effective in controlling mosquitoes. Traps using light or carbon dioxide will attract more mosquitoes than they kill, thus increasing the number mosquitoes in the area.
Even when their populations are high, a few simple actions can help reduce the nuisance effects of mosquitoes. While they cannot be totally eradicated from an area, their impact can be reduced.
Timothy Daly is Agricultural and Natural Resource Agent with Gwinnett County Extension. He can be reached at 678-377-4010 or firstname.lastname@example.org or http://www.gwinnettextension.com