Keeping Insect Invaders Out of Your House

For Southland residents, it’s an all-out year-round battle against a familiar enemy: hoards of ants, spiders, cockroaches, yellow jackets and grain moths who believe su casa es mi casa.

If you’re fed up with entering your kitchen each morning with trepidation, wondering what new creature you’ll find waiting to greet you, here’s what you can do to ensure that insects never invade your home again:

Absolutely nothing.

That’s because insect control is a never-ending battle. Chemicals do not last indefinitely; new bug cadres will quickly rise to replace the fallen. A speck of food left on the floor can provide a meal fit for a queen back in the nest.

No matter how hard you try, it’s virtually impossible to completely seal every hole, outlet and crack in your home. From a bug’s point of view, the smallest of openings provides an entrance the size of the Arc de Triomphe.

With most of us living in what should be a desert, leaving an outside door open for an instant can provide easy access for a rattlesnake or even a tarantula.

Whether it’s creatures large or small, the trick is to minimize the number of entries and then to use a select arsenal of exterior landscaping strategies, chemicals, nontoxic powders and general cleanliness to reduce the chance that insects will reside anywhere near your home.

Here are some experts’ tips on how to temporarily eliminate and control various insects in and around your house:

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Yellow Jackets

Always ready to ruin an otherwise perfect outdoor meal, yellow jackets increase the size of their colonies throughout the spring and summer.

Their nests are generally built into the ground, and the foraging yellow jackets can travel up to a quarter of a mile looking for your cheeseburger.

Although you may feel some sense of triumph hanging a yellow plastic trap in a tree and watching thousands of yellow jackets getting caught, you’re accomplishing virtually nothing, according to John Hurley, bee inspector for the Los Angeles County Department of Weights and Measures.

“You’ll fight them all season with those traps and get nowhere,” Hurley said.

The problem: The yellow traps sold in hardware stores are killing only the foragers, he said. But many more are being born simultaneously in the nest, which houses 10,000 to 40,000 that you haven’t yet seen.

The solutions: Eat indoors only or use a poisonous bait system such as micro-encapsulated diazinon, not generally available to consumers, that the yellow jackets will take back to the colony and feed to their neighbors. For more information, contact a pest-control company.

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Ants

If you’re a child of the 1950s, you probably remember watching armies of red and black ants battling it out on your sidewalk. Not anymore, thanks to the black Argentine ant, a South American strain that has established dominance in our area over the last 20 years.

Ants have become the most pernicious insect pest in L.A. area homes. And there’s no way to completely avoid them.

“If you live in Southern California, you’re going to have ants,” Hurley said. Sometimes lots of them. Argentine ant colonies often combine to form super-colonies with hundreds of thousands of members.

One upscale Baldwin Hills homeowner experienced that first-hand. Each morning, she found thousands of newly dead ants in her bathroom. Unable to trace them to their origin, she called the county. Hurley discovered millions of ants under the house; they were carrying their dead into this woman’s bathroom each evening.

Argentine ants thrive on sweet foods and fat. They’re particularly likely to invade your home during hot and dry weather, when they’re looking for cooler, moist climes.

“Ants have a large surface area on their bodies, so they become dehydrated quickly,” John Klotz, assistant entomologist at UC Riverside, said.

Entrance holes for water pipes, telephone lines or cable TV wires, as well as areas under window sills, make perfect entryways for ants. Caulk every hole in your house that you can find.

Cut down overhanging trees: Ants often make their way in by climbing across branches onto your roof. Keep kitchen surfaces clean and food-free. A tiny amount of food will keep them happy, even residue in a sink trap basket.

Immediately kill the first scout ants you see; if you don’t, one will return to the nest and, on the way, deposit a “scent trail” that makes it simple for other nest members to find their way to the food. Wipe your counters down with water to remove the scent left by the scouts.

When you see ants, you can kill them with window cleaner (if they’re near food) or with an approved ant spray. Window cleaner is slower, because it just drowns the ants; a commercial spray acts on the ant’s nervous system and also leaves a residual coating that will kill for several days.

It’s important to find the ants’ nest; only then will you have control over the population. Watch where the ants travel to locate their home. Once you do, you can dump boiling water on it or spray with a commercial solution.

Ant traps can also be effective; worker ants will take the poison back to the nest and feed it to other members. You may need to put a dab of honey on the trap entrance to get the ants’ attention. Traps may take up to three days to be effective.

Outside the home, consider spraying the perimeter with an approved insecticide, such as diazinon; it’s effective, but usually only for about a month.

Loath to use insecticides in your home? Diatomaceous earth (ground-up fossils) spread around the perimeter of a room or a house will create lacerations on an ant’s body, causing dehydration, but, like traps, it’ll take days to work.

You can also reduce ants by practicing “eco-landscaping”: Remove hummingbird feeders; the sugar solution brings in ants. Don’t carry firewood into the house, as you’ll be bringing along insects with it. Keep citrus trees far from your home: The sap created by the flowers is very attractive to ants.

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Spiders

“Control other insects in your home, and you’ll help control spiders,” said Greg Bauman, director of technical and field services for the National Pest Control Assn., the industry’s trade group. “That’s because spiders feed on insects caught in their webs.”

Spiders tend to weave webs in corners or wherever structural angles are present. Vacuuming of the webs can quickly take care of the problem. Though spiders do bite, “99% of them can’t get their venom into you,” said Eric Mussen, UC Extension apiculturalist. “If they do bite [with the notable exception of the black widow and the brown recluse], it will only hurt for a few days.”

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Meal Moths

What better way to successfully quell your appetite than to open your food cupboard to discover hundreds of white larvae clinging to your shelves?

They’re the early stages of grain moths, insects that feed on legumes, rice, flour, spices and cat food. They’re often brought in through store-bought food produced with poor quality control.

Trying to protect your food from infestation by placing it in plastic bags does nothing. Moths can work their way through even self-sealing bags. Use only glass jars with tight seals to store prospective targets.

Though grain moths love cereals, it’s unlikely you picked them up in a box of corn flakes. Large manufacturing plants seal up cracks in their factories and conduct frequent inspections to seek insects. If they find an infestation, they’ll destroy an entire allotment of cereal before it’s shipped, Bauman said.

If you open a package of food and you see what look like spider webs or unusual clumps in flour or spices, discard the package immediately by placing it outside the house. Leaving it inside means that new moths can still hatch, then typically fly up to 30 feet into another room to lay eggs.

Because you can’t safely spray insecticide into your food cupboard, the only way to eliminate grain insects is by carefully inspecting and discarding infected food, then removing all your shelves and wiping them down with a household cleaning solution. The tiny white grub larvae typically find dark, secluded corners in which to hatch, so you must be vigilant in your search-and-clean efforts.

Then, place grain moth traps in your cupboard. These emit odors that trap the adult males and interrupt the breeding cycle. Put newly purchased grains, such as whole wheat flour, in the freezer for several days to kill larvae.

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Cockroaches

They are one of the oldest and most reviled of pests, and Los Angeles can brag that it supports every variety: brown bandit, Oriental, German and American, the giant ones that Easterners call “water bugs.”

Roaches are famous for surviving on anything: coffee grounds, beer, even the glue that held the fabric to the rear of old TV sets.

An average roach can survive four weeks without food and two weeks without water, according to Bauman. So it’s essential to repair leaking water pipes and keep kitchens immaculate.

To aid in control, try boric acid spread behind kitchen appliances. A new approach is to use a combination of gel-based bait stations and a growth regulator spray. Each will produce results in several days.

The Straight Scoop on Insecticides

As are most industries, the pest-control business is awash in misconceptions. Here are the most common:

* You must hire an exterminator to get the job done right.

Not necessarily. Exterminators are trained and know how much of a particular chemical to apply and where it’s safe to use it. They can also formulate an overall extermination strategy, rather than reacting to an immediate crisis. If you prefer taking care of insects yourself, then do it. Just do it properly.

* The professional exterminators get to use the “good stuff” that’s not available to consumers.

Not true. “Most commercial extermination products are also available to consumers,” said Bauman. “But professionals know how much to use. If you use too much of a chemical, it will actually act as a repellent to insects.”

* The stronger a chemical smells, the more effective it is.

Not true. The noxious odors emitted from a can of bug spray are caused by the propellant, not by the active ingredients.

* Using chemicals is always dangerous.

Not true, according to every university entomologist interviewed for this report. What is dangerous is to use insecticides improperly. The printed instructions must be followed exactly. Do not try to kill ants with a product not labeled for that purpose. Do not spray a formulation in the kitchen or inside any room unless the label states that it is safe. Wear recommended clothing and goggles.

Eric Taub is a Los Angeles freelance writer.