mmpsteve
Real CZ's have a long barrel!!
Like LE said, get the powder and puff it in there good. Sprays aren't very effective as they don't get down in the nest well.
If you want to be totally environmentally unfriendly, a quart or two of used motor oil poured down the hole at night will do the job as well.
Out in the country at my Dad's place, we wait till night and pour a pint or 1/2 pint of gasoline in the hole and stuff it with a rag. You don't light it - the fumes permeate the nest and kill everything. It eventually evaporates, so I don't think it hurts the environment much, as far as leaching into the soil goes.
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