Repeat as necessary.
If you have badgers in the area they may dig it up and eat them.
We had a huge wasp nest in the gap where our blinds go - it was in an inaccessible area and right outside our sons room - we didn't fancy tackling it ourselves so called in the expert. I don't think it actually cost us anything.... or if it did then it wasn't much.
Smaller ones we've dealt with ourselves. Foam is great as it doesn't send them wild just stops them getting in. The killer sprays you have to spray and run.
Whatever. I sprayed a wasps nest with foam, within minutes they were writhing around and the next day there was a bunch of dead wasps on the sill and an empty nest. Sure you weren't using shaving foam?
She captures, stings, and paralyzes the spider, then either drags the spider back into her own burrow or transports her prey to a specially prepared nest where a single egg is laid on the spider’s body, and the entrance is covered. When the wasp larva hatches, it rips a small hole in the spider's abdomen, then plunges into the spider's belly and feeds voraciously, avoiding vital organs for as long as possible to keep it fresh. After several weeks, the larva pupates. Finally, the wasp becomes an adult, and tears open the spider's belly to get out.
reminds you of a particular movie?
here is the rest: http://en.wikipedia.org/wiki/Tarantula_hawk
Wasp foam would be my weapon of choice (also recommended by Obi-guy) which does kill them, but also is supposed to seal off the entrance. So apparently if you feel sorry for the little sods then you can foam spray the nest in the daytime when most are out and about and this will just stop them coming home. Spray in the evening /night time if you want to actually kill/suffocate them.
Hubby prefers to buy the super-duper spray stuff that you have to spray from about 10m away - because then they basically all die in an instant and I think he just likes to watch them die....
Are they these things?
Here is an interesting study that was performed on their control in Tasmania..... baiting with poisoned meat appears to be both the most effective, and most ecologically damaging (can't win 'em all)
Personally, from reading this, this would be my suggestion:
Go to a garden centre and purchase a granulated "Ant bait". Both wasps and ants are from the order 'Hymenoptera' so the poison should be equally as effective.
place the poison with a meat source, however, I would also keep the meat in a 'tupperware' container of some sort with holes big enough for the wasps to get in and out...... but prevent something like cats or dogs from accessing the meat.
Make sure the container is strong enough.
Use small amounts of meat and bait to minimise any accidental poisonings.
(and replace more frequently)
......... mostly, I don't think you have much chance in controlling these things.
The only thing I ever had success with was a can of fly spray and a cigarette lighter.
just burn the bastards as they fly out of the nest.... they get pretty agro, but if you've got a keen aim with the flame, you can burn off the wings from the worker wasps and the nest starves out.
Conclusion
learn to live with them.
This actually sounds like the go.
Except I would perhaps 'foam' the nest at night time when they are least active, AND you can trap most of the little blighters inside.
Just to see those creepie crawly flying things
They are not usually aggressive, but they are very defensive, and won't bother you unless you bother them. Even being close to the nest is not a problem unless you start messing with it.
We had a wasp nest on our balcony just above a door last year, didn't cause any problem, we still used the door and sat on the balcony, there was just always a few wasps flying in/out the nest and buzzing around.
Obviously this won't apply if you have the alien predator mutant zombie psycho wasps like they have in the films...
Are you sure? There are wasps in the cavity wall just behind my bedhead, husband insists that they don't re-use nests but it's the third year running! I'm assuming they're nesting in (and chewing, arghhh... the noise) the insulation so they could be in a section slightly further along. But only slightly....
Solitary species tend to lay just a few eggs and spend the rest of their adult lives foraging for food to feed the larvae.
They will sting if you disturb them, but if you leave them alone they won't harm anything, and could actually be beneficial for your garden.
If you could take a picture of one of the wasps up close that would help to identify what you are dealing with.
To be fair, I had also not heard of wasps that nest in the ground before either.
Could the OP also take a picture of the "Foam" stuff (if that is your weapon of choice - this interests me now)