Sugar syrup and boric acid. I made some bait traps using some 8-ounce Ziplock food storage containers...the little semi-disposable ones. There's a lip that runs around the top just below the actual lip that the lid fastens to...I cut slits right beneath that lower lip. At the end of each slit I "twist" the knife. With my fingers I bend kind of a "flap" that points outward and downward with the slit...this makes kind of an awning to keep rain out and also opens the slit up wide enough so the ants don't have trouble entering the container but still too small for the bees to get in. With the slits being so close to the top of the container the lid helps shed rain good, too.
The recipe is...all over the board. I've seen recipes of 1:1:1 sugar/boric-acid/water ratios....of 2 cups sugar, 1 tbsp boric acid, and 1 cup water, etc.,. I normally mix up a 1:1 sugar syrup and add a couple of tablespoons of boric acid per cup of syrup and call it "good"...seems to work ok for me. The trick is that you want enough boric acid to kill the ants but not so much that it alerts the ants and they shy away from it. You can also make a protein bait using boric acid and saved fat from cooking or peanut butter.
I simply pour about an inch of bait into the 8-oz ziplock containers and set them under the hive (I use cement blocks for hive stands) The ants will find it. Do the same with the protein traps....just be aware that if you have any "critters" roaming around your hives that they may go for the protein...I've had something (skunks I think) rip open a protein bait trap.
Cinnamon does work *sometimes*. I feel that it helps so I use it. I will sprinkle it on top of the inner cover and wipe it around good. I will also sprinkle on and around the cement blocks. Since I've used the boric acid bait traps I haven't had to use as much cinnamon.
Best wishes,
Ed
PS...I tried to use some elcheapo food containers from one of those Dollar Tree type stores but the plastic would rip to easily when I tried to cut the slits....ended up pitching those containers.