I bring up the topic of our little six-legged pest-friends, Argentine ants, because I myself, as I type for you every day, have been engaged in a weeks-long battle to maintain a perimeter of Orange Guard around my kitchen and bathroom against an invading army. As it turns out, ants invading homes are an annual problem in California, just one I hadn't especially noticed until this year — local media began noting an uptick in ant invasions last summer, as the drought worsened in August. But as Stanford ant expert Deborah Gordon noted in a study back in 2001, there's virtually nothing you can do to stop the ants completely, and it all goes back to the weather. "They come in because of the weather, and they go out because of the weather," Gordon says.

As CBS 5 noted last year, Argentine ants are all over San Francisco and the Bay Area — and if you heard Gordon on this awesome episode of RadioLab a few years back, they're part of a "super colony" that's been building along the West Coast for 50 years, extending between Oregon and Mexico, and waging constant war along distinct borders the entire way down the coast with native ants. And they dislike both wet, cold weather and extremely dry, hot weather, taking opportunities therefore in both winter and summer months to invade homes in search of water and nourishment.

And most pesticides are useless against them, so as Gordon says, "we're only harming ourselves" when we spray them — most pesticides are designed to kill ant species that colonize around single queens, but Argentine worker ants actually have many queens, and are free to return to any nest.

A pest-control specialist called in by my landlord here in SF said that he's seeing the uptick all over town this spring and it's tied to how little rain we got this winter — the lack of rain meant that eggs that would typically be destroyed over the winter never were, and the current ant population has therefore exploded.

So, what can you do to keep your kitchen from becoming a disgusting ant farm? There are a few things:

  • Orange Guard is human- and pet-safe, totally non-toxic, and made of orange oil. It kills ants on contact but also spraying perimeters with it, or areas where ants may be gaining entry, does do something to deter the ants from returning. But as I've found over about three weeks, it isn't a perfect solution and requires repeated effort — and there are other natural and chemical products out there that will have a similar effect.
  • Make sure sugar bowls are covered, dishes are promptly washed, and that nothing sweet gets left out on counters or tables.
  • Gordon says that most natural/herbal deterrents do very little to deter ants during infestations, and one of the only effective things you can do is to keep surfaces clean, and spray Windex along any ant trails that may be established, after they enter — ants are mostly blind and the reason they're following each other into your house is because other ants have left behind a trail of a pheromone-like substance that tells them there may be food ahead. The more ants that follow the trail, the stronger the "scent" becomes, and you end up with a hundred of them gnawing at a grain of rice that fell on the floor.
  • Also, she suggests, "Try plugging up holes in walls where ants might enter." I'd add that spraying the orange stuff under doors and windows seems to help too.
  • As for pet food that is easily accessible to the insects via the floor, Gordon says, "I also recommend building moats around pet food. If you put your cat bowl on a plate with soapy water, the ants won't be able to get across."

The good news is that ants don't carry diseases, and even if they're gross to look at they're not actually contaminating your kitchen counter or dining table as they traipse across it.

In battle, I salute you. And I'm right there with you.