Readers offer their advice on eliminating rats and ants

Time for some reader feedback on rats in cars and ant invasions.

DEAR JOAN >> I have had several very expensive repairs to replace wiring and to get rats’ nests out of automobile ventilation conduits and filters.

I set traps in my garage and caught several of them, but recently I Jiffy-Lubed my car and saw that they sold a product called Rid-a-Rat. I figured that, at $50 or so installed, it still had to be less expensive than my rodent-removal repairs. It was worth a try to get rid of the rats and prevent the horrendous, acrid charnel house stench that lingered in the car for months.

I’ve had it for several months and have not had a new rat or mouse in the car yet.

It supposedly works by continuously flashing little LED lights under your hood and is connected to your car battery.

— Lyrinda Snyderman, Bay Area

DEAR LYRINDA >> Thanks for the information. I’m betting Jiffy Lube will have a line of cars down the block when folks learn about this.

DEAR JOAN >> Your Nov. 22 column, “Brace yourself for the annual invasion of Argentine ants,” was very timely. Sure enough, the next morning they showed up in our kitchen and bathroom.

We live in the South Shore area of Alameda, a community that was built on a former sandy strand of beach. It has been described as one big ant hill, with interconnecting colonies of Argentine ants that defy any long-term control.

Years ago, my next-door neighbor, Larry, a pharmacist, gave me his formula to control them. It is basically a sugar and boric acid solution that you put in a shallow container and set at a spot where they are trooping. They swarm over it, imbibe and in three days they are gone. Of course, they will be back.

A caveat and some refinements: We do not have young children or pets. If you do, I would advise against using this. An open container of sweet liquid could lead to disaster as boric acid is toxic if ingested. It is not corrosive nor toxic to skin contact.

You can buy boric acid powder at many pharmacies off the shelf. I sterilize the glass container for the newly made poison and store it in the refrigerator. This prevents the growth of black mold in the container. Be sure to put a poison label on the container.

After a few days, the solution in the traps will dry up; add water or put out a fresh trap, if needed.

This is a relatively ecofriendly way to control these ants. It does not eradicate them from their habitat outside and makes it possible for me to avoid more toxic insecticides, while controlling the swarms that invade the home. They have not become resistant to it; they actually seem to halt their invasions sooner the more often it is used.

— Roger Ecker, Alameda DEAR ROGER >> Thanks for the tip, and I’d just add that this solution should never be used outdoors, as the sugar in the formula will attract a good many creatures that would be harmed. But indoors, given the caveats you mention, is OK.

There are a lot of recipes for the ant bait. The one Roger uses is 4 teaspoons boric acid, 1 cup sugar, 3 cups water. Heat to dissolve.

Put cotton or plastic foam on top to give ants a platform from which to eat.