Unable to locate yellow jacket nest/ground entrance - any tips?

Probably under a bush. Those little bastards are sneaky.

I found them today while riding my mower.

Fortunately, I noticed them swarming before going back over them for a second time.

Foaming spray at dusk.

I found two nests while bushhogging my place last week, or they found me rather. Got hit 6 times between the two. Waited until after dark while they were all in the ground, filled a water bottle with gas and turned it up into the hole.
It has been my experience that their holes are usually near (within a few feet) a tree, bush, etc…. I have found them in the wide open, but very seldom.

On a related note, a yellow jacket nest that was active in my yard in July, seems to have no yellow jackets around now. I did not spray the nest either anything

Was walking the dogs the other day and they got into a nest under a pine tree. They started doing the whirly birds and cartwheels. Then they ran to me. Been a while since I’ve done the 40. Them things are born PO.

When they're really active you can creep up on a few and throw baking flour on them. It makes them go slow as frick, easy to see (white) and they almost always immediately return to the nest.

You also look hilarious doing it. My wife filmed me doing it from the house and it looked like I was just throwing pinches of flour randomly in the air for 10 minutes.

ETA:

I have a 50% success rate with this as well, just FYI.

WITW did I get dv’d? My method is unorthodox, sure, but I’ll keep doing until it doesn’t work + this way I don’t have to pour poison all over my yard.