Many areas of Iowa have had flooding recently, but Iowa State University Extension Entomologist Donald Lewis says it doesn’t mean mosquitoes will be swarming immediately.
“It’s not the floods that cause the mosquitoes. In fact, flooding (and) heavy rains frequently initially depress mosquito populations, but if the water stands for seven to 14 days following that, then mosquitoes can breed in those temporary water impoundments and populations can build fairly quickly.”
With saturated soil, Lewis says continued rainfall that keeps water from draining out of roadside ditches, potholes and other areas will lead to mosquito growth.
“Certainly if you’re having a graduation party or a wedding reception — if you’re going to have a backyard barbecue, you can fog or you can have your backyard sprayed for mosquitoes and it will help reduce the population for a day or two, but all those untreated areas right outside your property are still teeming with mosquitoes in an outbreak year,” Lewis says.
“They will quickly move into the area that’s treated.” Last year’s drought caused mosquito numbers to be at record lows in Iowa, according to Lewis. He says the best defense against mosquitoes is to apply mosquito repellent to exposed skin.
By Dennis Morrice, KLEM, Le Mars