Your Money Adviser
By ANN CARRNS
With summer in full swing, mosquitoes are buzzing in backyards — and fliers for residential mosquito control services are swarming mailboxes. Should homeowners bite?
Depending on where you live, those fliers may come from Mosquito Joe, based in Virginia Beach, Va., or from traditional lawn treatment companies like TruGreen of Memphis. Both are expanding their services. Companies of this type typically charge either a monthly fee or a fee per treatment, which usually occur every three to four weeks.
The cost of the services varies, depending on where you live, the size of your yard and other factors, like whether your property has lots of dense shrubs and greenery that might harbor resting mosquitoes. Companies tend to offer a discount for the first treatment, then charge a flat fee per treatment, usually in the range of $40 to $70. The total annual cost depends on the length of the mosquito season where you live: shorter in cooler areas, longer in the South.
Residential services typically use insecticides registered with the Environmental Protection Agency, like pyrethrins, derived from chrysanthemum flowers; and pyrethroids, synthetic chemicals that mimic pyrethrins. The treatments have become more common as the use of organophosphate pesticides, which can be more toxic to birds and animals, has been scaled back.
Employees of mosquito control services generally blow an insecticide from a backpack-style tank, targeting the underside of leaves, vegetation, ground cover and other cool, dark areas where mosquitoes lurk. “The treatment we do is targeted,” said John Bell, a registered entomologist with TruGreen. The spray generally kills the mosquitoes that it touches and then dries, leaving a residue on leaves and branches that repels bugs, he said, helping to control insects that fly into your yard from elsewhere.
The E.P.A. says registered compounds are safe and effective when they are prepared and applied according to their labeled use. Still, the agency’s website notes: “No pesticide should be regarded as 100 percent risk-free.”
Mosquito control companies usually recommend that children and pets be kept inside during spraying, and for 30 minutes to an hour afterward. Pyrethroids can be toxic to bees and fish, the E.P.A. says, so treatments should avoid decorative ponds.
Before paying for a monthly service, you should consider whether you need it, said Joe Conlon, a technical adviser to the American Mosquito Control Association. Local governments and mosquito control districts may periodically dispense insecticide from trucks in areas with dense mosquito populations. Last year, there was an aerial spraying of insecticide in South Florida because of concerns about the mosquito-borne Zika virus.
To find out what control services are conducted in your area, check the map on the National Pesticide Information Center website.
Residential systems that automatically spray pesticides once or twice a day, from nozzles attached to fences or buildings, are becoming more available at a cost of as much as $4,000 or more. They generally use E.P.A.-registered insecticides, but the delivery systems haven’t been studied enough to conclude whether they work, according to the agency’s website.
A concern with automatic systems, Mr. Conlon said, is that overeager homeowners may dispense more insecticide than needed, resulting in over-spraying.
The National Pesticide Information Center has more information about mosquito control, and tips for hiring a pest control service.
Here are some questions and answers about mosquito control:
What steps can I take to reduce mosquitoes around my home?
Mosquitoes breed near standing water, so it’s important to regularly dump water from buckets, old tires, flower pots and even toys like Frisbees. The E.P.A. and the Centers for Disease Control and Prevention recommend changing the water in birdbaths and wading pools every week to help reduce mosquito populations. Having gutters cleaned and covering rain barrels helps as well.
Do “all natural” mosquito control options, like peppermint-scented sprays, work?
Evidence that such sprays effectively repel mosquitoes when applied outdoors is mostly anecdotal, Mr. Conlon said. Homeowners who prefer natural sprays could try them to see if they help, he said, and then switch to a registered insecticide if needed.
Should I spray mosquito repellent on my skin when I’m outdoors?
The C.D.C. says repellent sprays containing the compound DEET offer the best protection against mosquito bites and are generally safe if used according to instructions. The agency recommends that the sprays be used only outdoors and that people wash their skin with soap and water after going inside.
Consumer Reports recently tested several so-called natural spray repellents and recommended at least one, Repel Lemon Eucalyptus. The product hasn’t been comprehensively tested on children, however, and shouldn’t be used on those under 3, the magazine said.