I was told this by an old timer, and I am sort of old myself. To kill ants, don't know which kind, mix some syrup and yeast and pour it on the mound or where the ants are. In theory, they will eat the mix and swell up and die. Might be true.
I have also heard that ants have several queens on stand by, and if the main queen dies, they wake up the next queen in line and tell her to get her butt busy producing. Sounds logical, once you think you have killed the mound, several more pop up.
I have also thought of electrocuting those fire ants, by using a large neon sign transformer. It will draw a 3 in arc.
For yellow jackets, I got stung bad one time and I swore vengeance. What I did was to get one of those large bug zappers, and hook it to a long pvc pole, plug it in, and placing it by the nest and jiggle it a little bit. It was something to watch. The first one that gets killed, gives off a scent and the others go to that scent to help attack. Guess what, they attacked the bug zapper, and it smoked ever one of those little bas####.