Mosquitoes - Part II

Like I said last week, although we would like to have some sunshine for a little while, I am a believer that we will need and want more summer rains.  When we do receive more rain, here is how we handle mosquito control at home and around town after a hard spring and summer shower.

Nuisance Floodwater Mosquitoes

Floodwater species become a problem seven to ten days after a rain.  Higher water flow and water collection in normally dry areas stimulates egg hatch and development of these mosquitoes.  After developing into adults, floodwater mosquitoes are generally only a nuisance for a week or two because of their short life span.  However, many species can cover twenty miles or more in search of a food source.  Local floodwater species usually come from the flood plains of nearby creeks and rivers, roadside ditches and other area drainage ways and flooded agricultural land.

Wood and floodwater species often utilize cavities in trees that can receive enough rainfall or water from sources such as sprinklers as breeding sites.  The adults of the woodland species emerge and become a nuisance in a similar time frame to floodwater species.

Artificial container floodwater mosquito species prefer such items as jars, cans, tires or any other item that can hold sufficient water long enough for breeding, usually longer than three days.  These mosquitoes are frequently a major source of backyard annoyance in urban areas.  Adults tend to remain very close to their breeding sites so removing these containers is a good control method.

Prepare to live with Nuisance Mosquitoes

Expect population growth of floodwater species seven to ten days after a rain.  Try to schedule outdoor activities away from early morning and late evening as these are the major feeding times for mosquitoes.  Use repellants if these activities cannot be rescheduled.

Do not use “bug zappers” as mosquitoes use light to navigate.  Once a food source is detected near a light, the light is then ignored and mosquitoes concentrate on the food source.

Remove all trash, jars, cans, bottles, tires and all other items that can collect water and provide a breeding site.  Keep rain gutters free of trash and standing water.  Keeping grass and weeds mowed will also reduce breeding sites as water collecting in depressions will be exposed to wind and sun and dry quicker.

Fogging or spraying garages, sheds, shrubs and grassy areas with an approved insecticide (permethrin, cyfluthrin, etc.) will help eliminate mosquitoes resting in these areas.  There are many products approved for use by homeowners against adult mosquitoes.  These products are available at local farm supply and retail outlets.

Inspect window screens and screen doors for gaps and areas in need of repairs.  Make sure screens fit properly and exclude mosquitoes from entering dwellings.

Some good information to help you manage mosquitoes can be found at http://mosquitosafari.tamu.edu/.

The newest information on repellents can be found at http://cfpub.epa.gov/oppref/insect/.