I've also noticed here in Berkeley that indoor Argentine ant invasions just haven't happened much this summer, nor last winter during the rainy season. It may be premature to say they wont be a problem again with the start of cold and winter rains this fall. Outdoors in the garden I haven't noticed any lack of Argentine ants, they are still everywhere in the garden, doing the usual damages by spreading/protecting scale on things like Abutilons and lemon trees, setting up nests in container plants and underneath flagstone/brick/concrete paving areas. They seem just as plentiful outddors as ever, but it is mysterious why they haven't been trying to get inside the kitchen this year so far.

Come to think of it, we haven't seen any ant invasions this year either.

But we've had several invasions of cluster flies inside the house. Fortunately, they're slow and easy to swat, catch, or spray with window cleaner that kills them on contact.

I have had numerous amounts of the little black devils in my yard since I moved into my house 10 years ago. At first when I would spray out back they would end up in the house which was even worse. Over the years we kinda worked out a truce where if they stayed outside I would leave them alone.

All was fine for the most part. Every once in a while they would try and move inside and be dealt a hard blow. This arrangement seemed to be doing OK until a few weeks ago when we were having a pretty good heat wave. Although they had not been in the house I noticed more and more trails making there way across my patio. Then one night it changed from a few trails into many superhighways between 1 and 2 inches thick.

Now the truce was over. I put the dogs in the house and grabbed the one gallon jug of pump action Spectracide and went all Rambo on them. I was ready for Part two - First Blood in a few days but so far I have not seen one since. I'm now left wondering how long they will keep themselves barricaded before wave two begins.

I hadn't given it any thought 'till now, but have not had a single problem in house or garden with ants .... ditto for dog food left out, not having any ants.

[eerie music] have they read the Mayan calendar ... leaving before THE END ?

Posted by: laa_laa -- "This started me thinking...I haven't seen an ant this summer. We have not sprayed or used anything different....A friend also said they had not seen the ants. After 30 years of ant invasions, I am a little worried....Does anyone have an explanation? "
===
Don't worry. Now you've jinxed it :)

My explanation is temperature, it's simply been a cooler year and I've seen fewer ants, aphids, scale and a few other pests, I think in part because of their cold-bloodedness. just a hunch though, no proof.

My acceptance that I temporarily inhabit Argentine ant territory is complete, I'll never get rid of them as long as I share a wall with trailer park dumpsters. Doesn't mean I won't fight skirmishes with them though when their numbers skyrocket, but they have to be the most successful in a long line of invasive species in CA, huh?

Thanks for your replies.
It is interesting to find that I am not the only one with a scarcity of ants. I was remembering that I heard once that if you have argentine ants, you won't have termites. I think I read it on the Gardenweb site, but I'm not sure. I would much prefer the ants.
Also, a few years ago, we had some squirrels rather abruptly leave our huge Stone Pine in front of our house. A week later, the tree fell over. We figured that the Stone Pine's roots had begun to grow in a circular type of swirl instead of growing down, because there was an unexpected patch of hard-pan near the surface. If the squirrels deserted because the roots were no longer holding on the tree, what type of disaster might the ants be predicting?
At least I know (can hope) now that it is not a phenomena confined to our property.
Lina

Not just the ants flies,bees ,wasps, mosquitos,butterflies virtually ALL BUGS are disappearing and dieing off. James ( In London UK)

yes, I have not seen ants hardly at all this year and the decrease started a year or more ago.

I saw a few at the beginning of the year that live under my driveway in Redondo Bch

and they looked very thin and smaller than usual. I believe they have been affected by all the

Chem trail spraying. It drops on our cars and the very fine reddish dust is not a natural

presence in gardens. Some have analized it. It contains aluminum .

I used to see ants farming this small slow moving bug that lived on my lemon tree branches

and also they would farm or move a fungus like goop that formed on my lemons,

now all that activity is gone! gone like it was never there. I use no poison of any kind.

But termites are still around.

I have had the opposite..after they went away 5 or 6 years ago?..They are now back. Not sure what I was doing then that made them take a hike..but the Argentines are back and trying to nest in houseplants - but crushed fresh garlic spread on the pots drove them back outside.

You do know all the Argentine ants in California are in DNA,one colony of over a trillion ants.

How do you kill that off?

Ants left because of the wether i think