try boric acid.
google " boric acid, kill, ants".
Homemade bait stations
Since commercial baits based on boric acid are relatively inexpensive most
people opt to purchase the actual boric acid bait rather than make your own
(see below). However, you'll first want to use unbaited (no boric acid) food
stations to locate and "train" the infestation. You can make the unbaited
stations yourself.
Unbaited stations can be made from jelly, honey or even sugary corn syrup
like Karo Syrup (tm). A small amount of vegetable oil can be added to the
syrup for times when ants seems to be more interested in fats than sugars.
You'll need to adjust the fat/sugar ratio depending on your own observations
. Most of the time 100% syrup baits work fine. If ants seem to be ignoring
the bait stations try adding a little vegetable oil (see How To Control
Nuisance Ants).
Put feeding stations consisting of a small amount of ant food on a piece of
waxed paper where you observe ant activity. Ants will feed and become
trained to this location. When the colony is actively feeding you can
replace the food stations with baited stations.
Commercial ant baits
Ant baits can be purchased online (Bait Info) and at lawn and garden outlets
. Terro (tm) is a popular commercial liquid ant bait and is effective for
most household nuisance ants . Borate-based liquid ant baits are low
toxicity and very effective but may not eliminate large colonies. The aim is
to suppress colonies a few times a year. Since these ants pose no threat to
the home's structure, complete elimination is usually not necessary.
