How to get rid of ants attacking tree?

get rid of ants
Alex N asked:

We just purchased our first home and have a mature peach tree with a well established ant colony in the branches. The ants are eating the peaches, and we can’t figure out how to get rid of them. We tried a few different baits, but they didn’t take. I’m not sure what kind of ants they are. I’m assuming ant bait would be best but I’m not sure which kind or how to place it. Any suggestions would be appreciated.