Your new house guests are giving you the creeps, whether it’s that mouse you saw snacking on crumbs in your kitchen or the mystery creature you killed the other day in your basement. (A roach? Godzilla?)

Before you hire an exterminator to handle a pest problem, learn what you can do yourself. You should be able to cure most issues, other than termites and bedbugs, without hiring a service.

The first step is to prevent pests from getting what they need to live and reproduce. This often requires no pesticides; you can maintain a clean kitchen, vacuum frequently, eliminate water leaks and seal possible entry points.

For persistent problems, homeowners often say they want “green” or “natural” pest control. And many companies claim to practice it, or they offer alternative treatments. But is it real? And does it work?

Some effective nonchemical extermination approaches have been used for years. Rodents can be effectively controlled by closing off entry points from the outside and placing traps in strategic locations. Humane traps are available for relocating, not killing, rodents.

Small ant infestations can be controlled by caulking cracks and other access points and using soap and water to wash ants’ travel paths, erasing the scents they follow to food sources.

The most effective remedies for bedbugs often don’t involve pesticides. Wash your clothes, sheets and blankets in very hot water; get your carpets and rugs professionally cleaned; thoroughly and repeatedly vacuum probable hiding spots; and use isopropyl alcohol to wipe down furniture, walls, pictures and other belongings that can’t be cleaned in a washing machine. (Isopropyl alcohol destroys bedbugs and their eggs.)

But be wary and skeptical of any pest-control service or product that markets itself as “green.” Checkbook has found that many companies that claim to provide natural solutions employ the same pesticides and methods used in conventional treatments. We’ve even heard of companies that claim to be “eco-friendly” because they recycle office paper.

Even if a pest-control method is labeled “natural” or “nonsynthetic,” read safety labels carefully; companies should supply them, upon request. To learn about a pesticide, check the Environmental Protection Agency’s pesticide selector website at epa.gov/insect-repellents. You can also find information by doing a Web search for the name of a pesticide or chemical and the word “safety.” If you find a notice that an EPA review is underway — or that researchers or citizens’ groups are urging one — it’s a red flag.

“Natural” is an ambiguous term, and nonsynthetic pesticides can still be harmful to your family and the environment. Some products derived from natural sources aren’t any safer to humans, pets, wildlife and beneficial insects than their synthetic equivalents. And some natural products must be applied more liberally than synthetic ones to achieve similar results.

For example, many pest-control companies consider boric acid an alternative, natural insecticide. That’s a rather dubious claim; exterminators have been using it to control roaches since the 1940s. But boric acid does have very low toxicity to humans and is safe if applied properly. (Avoid inhaling it, use small amounts and focus on applying it to areas where insects live and travel.)

Pyrethrum is another commonly advertised natural pesticide alternative. It’s the naturally derived form of pyrethrin, which, like boric acid, is deadly to insects, but has very low toxicity to humans and other mammals. Pyrethrum is extracted from chrysanthemum flowers; pyrethrin is created in a lab. Although each product has the same effect on insects — and presents the same risks to beneficial insects — pyrethrin usually is more potent and lasts longer. So using the natural form of the pesticide often entails applying it more often and more liberally.

Another option for controlling roaches is sticky traps, which will probably put only a small dent in a moderate or large infestation. Some companies will vacuum roach-infested sites to capture many bugs and eggs and knock infestations down to levels that can be managed with sticky traps.

Peppermint and rosemary oils, which repel or kill many types of insects, also might control roach, ant and some other insect infestations, but they must be applied often. They’ll eliminate stinging insects, but as an exterminator once told me: “It will kill them, but not as fast as other products — not nearly fast enough if you’re the one doing the killing.”

To exterminate wasps and hornets, instead of using pesticides, professionals can knock many types of nests to the ground and crush them. Bees’ nests can be relocated. (Unless you own a bee suit, don’t try to DIY these jobs.)

Finally, some companies offer to encase your home in a tent and pump in hot air until the temperature reaches 120 degrees or higher, destroying the insects and their eggs. This process is very expensive (thousands of dollars for an average-size house) and disruptive (residents have to remove anything that could be damaged by the heat and live elsewhere for a few days). Also, the amount of energy required to heat the home to 120 degrees could theoretically disqualify this procedure from being “green.”

If you do end up hiring a pest-control service, shop around. There are significant differences in quality, and you don’t have to pay more for good service.

Checkbook found big company-to-company differences when it asked area consumers to rate pest-control services they had used. Some outfits were rated “superior” overall by 90 percent or more of their surveyed customers, but others received such favorable ratings from fewer than half of their surveyed customers.

Get multiple estimates. Checkbook’s undercover price shoppers found a wide range in prices, and there was no relationship between what companies charged and customer satisfaction. Some companies charge $175 or less for a single treatment for cockroaches, while others charge $300 or more. Some push annual contracts that cost $400 or more, even though, for most pests, a single treatment done well should suffice. Avoid getting and paying for applications you don’t need.

If you think you have termites or bedbugs, it’s especially important to get multiple proposals. Some companies recommend treatment when there is neither an active infestation nor a serious threat of one. For termites, ask whether they recommend treating only part of your home or its entire perimeter; you’ll save big if a company can wipe out your infestation without a house-wide treatment. To treat a small termite infestation, companies quoted prices ranging from $600 to $2,000 to Checkbook’s undercover shoppers.

For any kind of critter, get your guarantee in writing and check what it offers: Will the company pay for additional pest damages or just retreatment? How often will it come out to inspect at no extra charge? And what do you have to do to keep the guarantee in effect?

Brasler is executive editor of Washington Consumers’ Checkbook and Checkbook.org.

Washington Consumers’ Checkbook magazine and Checkbook.org is a nonprofit organization with a mission to help consumers get the best service and lowest prices. It is supported by consumers and takes no money from the service providers it evaluates. You can access all of Checkbook’s ratings of area pest-control services free of charge until May 10 at Checkbook.org/WashingtonPost/Pest-Control.

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