How do I destroy a wasp nest?

Petrol has failed. Twice. Petrol has always worked for me. They are very defensive now. What's the next step?

Are you aware of the what species? They are ground nesters right?

Known as a German wasp, Yellow jacket or Vespula germanica.
Nesting in ground on a vertical bank.

You can flood it with soapy water.

Yes. I can siphon water down from the deck into the nest. I can use used grey water from the washing machine. The difficultly is in getting the hose into the hole at night. I will need a flashlight to see the hole. When I feed the hose into the hole at the nest entrance, will they all come out at night and attack me?

Probably, but they'll have difficulty seeing you and if it's cold you'll likely have plenty of time to insert the hose and run away.

It is not cold in the North Island of New Zealand.
Still warm.
I'll do it.

Cooler than during the day I meant.

I see. I could do this at night as it's cooler or pick a colder night. They will be less active.
Is that right?
I am collecting used grey-water from the washing maching for this. One day's lot should do it.

Wondering if anyone had tried dry ice for this. Perhaps they need almost no oxygen once they have hibernated from the drop in temperature.

We have them and they will attack you at night also. I lived through this experience a few times and being stung several times, not very good at all.
The ones we have are very aggressive and they will swarm with temps in the 30`s f. Not that I like to destroy them but at distance plug the hole with a bottle of poison turned down into the hole and leave it, then run for your life.
Good luck either way,,
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They defeated me a third night. This morning, instead of dead they are business as usual. Perhaps the hole I assumed to be their entrance is not the main entrance or not an entrance. The entrance is hidden in a bank under long grass. I plan to go tonight with snippers and trim away all the grass in an effort to find the entrance. A dangerous exercise. Or I could light a small fire on it.

Well that sounds about right. At our farm I stopped a tractor on top of a ground nest and they were all over me, had a bunch of very bad stings.
Plug the hole would be a good start but that will not kill them.
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Like I said the ones we have will swarm at night, and do not think twice about it. Vibration is a key, ground vibration can be picked up by them a good distance out, so stay at a distance. At one time I was going to buy a suit to dress up in to keep them out and then gas them. I finally tossed a gas bomb at the hole and then filled it up with the liquid.
I usually do not bother them unless they are in areas we travel like around our pond dams.
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Still, they're much less active and alert at night. Their defensive behavior might not change that much at night, but the cooler temperatures slow them down significantly and although vibrations are what triggers them to attack, they rely on visual cues to find their target and they can't see you as well in the dark.

Doesn`t get cold enough in my area to slow them down. 82 degrees f. in January and some cold nights. I have been dealing with yellow jackets a long time, the underground chamber temperature must also be taken into consideration which is a lot higher in the hot south after a freeze above.
I tried a cold morning which did not work that good. I have been stung many times.
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