I had that problem a few years ago and my pest control people suggested "over and out" I used it very successfully to rid the ants from my roof, which they were consuming. Also rid them from a tree.
Do it Yourself Pest Control also has products.

Be careful of the red ants! That sounds like a red velvet ant and they are extrememly painful and poisonous.

Girlgroupgirl,

Thank you. I have had it wit these ants. They are all over my hydrangeas, trees, and I worry about my dogs and family when they are in the grass. Especially now that I saw Karma4111's post!

I will look this afternoon at the Lowes or HD. If over and out is not available there, where do you recommend I go?

Kathgrace, looks like both Lowes and HD should carry it. Here's a list of other retailers. I'm going to try this too, we've been battling ants ever since we bought this house.

Girlgroupgirl, thanks for the suggestion.

Here is a link that might be useful: http://www.gardentech.com/ono_wheretobuy.asp