Don't do anything during the day. At night the nest is mostly inactive. Since it's attached to the house, kill with fire isn't the best way. Easiest thing to do is go pick up some raid wasp/hornet killer. It's pressurized to shoot up to 15 feet. Wear long pants, a hoodie, gloves, etc. Don't get directly under the nest, but close enough that you can clearly hit it the entrance with some raid. Dump a can on it. Then go back inside and let the raid do it's thing.
The raid won't kill everything. So you will need to go back out the next day. Knock the nest down, hit with raid again, go back inside for the night.
Go out the next day, pour a starter trail of gasoline on the ground, pour some on the nest itself. Light, celebrate victory. Let that shit burn until it extinguishes on it's own.
Raid whatever is left.
I've always been "lucky" in that the yellowjackets I've dealt with have always been in the ground. So I typically find them when I'm wearing shorts and cutting the grass. The most recent time was last summer when I ran over a nest with Noah outside. I was screaming at him to run inside the house as I was getting mauled. He panicked and just stood there crying so I had to grab him, carry him into the house, and yell at him to run upstairs and wait. The whole time my legs were covered with yellowjackets. Amazingly enough he didn't get stuck. I on the other hand, should have probably gone to the hospital because I got hit about 40 times and was having shortness of breath. I just choked down about 5 benadryl and laid on the floor waiting for my wife to get home.
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