My 10 acre field is overrun with Groundhogs, They make mounds so high the mower gets hung up on them. This year they gotta go, so my intent is to find ALL their entrances, and then eliminate the groundhogs.

I would like to make smudge sticks or smoke sticks, stick them down the known holes, and mark where the smoke comes up. I have a quantity of tent pegs with bright orange tape tied to them at the ready, and my plan is to watch the field for smoke, and go to where the smoke is exiting the ground and mark it.

Can anyone advise me on how to make a stick that makes very visible smoke.