I found a large pile of sand alongside my concrete driveway. It was under some evergreen hedges that grew a long the driveway, and it was not readily visible. The sand pile was was maybe 3"-4" high and about 12-14" diameter. I have used axle grease successfully on carpenter ants in the past, but I couldn't put that down the opening I found. So I poured about 1 1/2 qts of heavy motor oil down the hole. The next day I found a dead bug at the whole opening. It was very large - maybe 1 1//4 inch long and as big around as the end of my little finger.
I have been told by some friends that it was probably a Cicada Killer. Do you think that is right? What else could it be? Do you have any suggestions on what else I might use to permanently kill any other bugs that are in that hole? Thank you.
Saginaw County Michigan
Based on the sand piles and size of the insect, it is most likely a cicada killer. In the future, I would advise against pouring motor oil down a nest hole, since this can cause chemicals to leach into the soil or groundwater. Only 1 wasp nests in each hole. If you can tolerate a large buzzing wasp, there's no reason to control a nest that is not causing damage to lawn. These wasps are large but not aggressive and are searching for a cicada to bring to their nest rather than a human to sting.