SPIKER
Elite Member
That's what I was thinking, may have to flood them out. If the 7 doesn't work maybe a little Diesel since it will have some residual properties.
I usually use a bottle (12 oz plastic pop type) about 2/3 full and shove the open bottle into the hole to seal up the gas into the hole and the gas turns to vapor killing anything left in the hole. leave bottle sealing the hole for a day or two as well. this is my method for yellow jackets but never tried bumblebees though...
other method is a weed burner when they are more aggressive just fry them hole & all it will pull out all O2 and kill & overheat them if they are deep under ground.
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