It's that time of the year again when fire ants and crawdads start building mounds and hills all over our yards.
I have accidentally found what I think is the perfect solution:
Melt the mounds/hills back down to soupy mud using your garden hose! It's successful and even exposes the grass underneath, allowing it to recover rather than being killed and leaving bare spots in your yard. The mounds just thoroughly melt and disappear.
Keep flushing the mud for about a minute after the nest is dissolved. This flushes the soupy mud completely down into the nest tunnels, which seems to trap and kill the nest occupants all at once. I don't have a problem with re-emergent nests five feet away, which was usually the case when I tried to use a poison to control them.
This method also works well when dealing with an ant nest around the roots of your garden plants. Just dissolve the nest with your garden hose. The mounds don't directly harm the plants, but the tunnels they build aerate the roots which does harm the plants.
When the nest is dissolved around the stems of your plants and mud refills the tunnels, that problem is solved. At least, that is my supposition, and I know of no other way to get rid of those mounds around the plants.
It's free and doesn't use poisons, but there's also no mess, no real effort and the mounds/hills are gone. What more could you ask for?