I was trying to clean out a bunch of overgrown nandina when I dug right into a nest of bees underground in the roots. How do I get rid of these so that I can finish getting rid of the nandina?
Wasp/bee spray at dusk, spray it into the hole. Be prepared to exit quickly (I'm not saying they will chase you, but you don't want to hang around just in case, right?). Has worked for us on yellow jackets several times.
Gasoline and a match at dusk.
gasoline without the match at dusk
One recommendation from the County Extension Service was at dusk, lay a sheet of window screen over the ground where the nest is, then spray. Even if you can't get the screen flat to the ground, it should slow the wasps or bees up enough you can get out of range.
The last ground wasp nest we had was about a two foot diameter sphere that was "discovered" by some workers clearing trees. I drove in to pick up some wasp spray. When I got back there were six men with 30 feet of old galvanized pipe, pouring gasoline into the hole. One of the men had been "elected" to go make sure the end of the pipe was in the nest. I think they picked him cause he was the fastest runner, LOL!
It worked though no one could go to that area for a couple of days due to the surviving wasps still hanging around. I believe that at dusk they would return to the gas soaked nest and more would die every night.
Hmmm- I think I'll try poison first. I like the screen idea. I'm scared to pour gasoline in this drought- this is very close to the street and one smouldering cigarette or wheel spark could set the surrounding trees on fire.
The only problem is that the nest is right under the roots of the bush, and it's impossible to see exactly where the entrance hole is. Also, I think I demolished it/ created several new holes when I was trying to dig up the bush. Oh, woe is me- honeybees are dying out but ground bees are thriving under my nandina!
I had my pest control guy spray a yellow jacket hole once. He pumped 2 canisters of wasp killer in that hole - the next day those jackets were madder that a flock of wet-hens! I got stung on the top of my head 6 times!! No more gardening for that day-ouch!!
It only takes a very small amount of gasoline to kill them.
I've eliminated 6-8 nests over the last 20 years. The easiest way I have found is to use the long range wasp killer spray. Dusk is good.
Orthene fire ant killer at the entrance also works well. Unfortunately, you have to get right up next to the entrance to sprinkle it so wait until they have calmed down. The yellow jackets leave and have not returned to the same place.
I don't like the idea of gasoline. The yellow jackets I dealt with were right near/under my plants. I also had a nest in my compost pile.
buy some sevin dust and take approx. a 1/2 cup to cup of it at dusk and in and around the hole. They will be gone in the morning.