Ants taking over my yard.

[Kiltman]

I let my chickens roam free in part of my yard and the grass area is now being overrun with tiny black ants. Before I had chickens I would put out some Amdro for them to take into the hive to kill the queen, but I refuse to use it now with the chickens having access.
How do others combat ants in their yards that will not cause harm to the chickens?

 

[MadamContrary]

Boiling water on anything that's not near plants I want to grow. Kills the whole hill, no chemicals. Chickens will eat the bodies. Win-win.