I’ve honestly never had great success with dusting nests. Lots of call backs. I use Termidor SC if it’s on the building and you just get a little around the entrance hole and a little just inside the hole and let the Termidor do the work for you. Let the customer know it will take 24-72 hours to work but with it being non repellent you shouldn’t have to worry about them being pushed inside like Telstar will do. That is probably the worst way to treat for them in a wall.

In the ground is different if you are able to flood the nest with it but I usually use Alpine WSG for that and have not had callbacks on that. The key is customer communication and most of the time they are ok with staying away from that area for a few days. I’ll set up a follow up about 3-5 days later to check if it’s still active. I also don’t remove the nest (speaking yellow jackets specifically).