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How to flush out a groundhog Answered

Alright I have a real problem.A whole community of groundhogs has just made its home in my dams retaining wall. I have counted around five separate holes in the wall and have tried to smoke them out with around 5 separate smoke grenades, but apparently the tunnel system is much like the Viet Cong and are just to vast. I need to nail these rodents ASAP before they break through. Any help would be great thanks.


Get yourself a 10 foot piece of 1 inch diameter, thin wall plastic black tubing. Like what is used for shallow well pumps. Double up an old sock and place over the one end. I also use a newspaper bag with holes in it, tie it on loosely over the sock. Carefully push the sock covered tube end down into main Groundhog entrance, push in without pulling back on tube. Shovel dirt around tubing and also cover secondary entrances. Place a funnel in open end of tube and carefully pour in a quart of Ammonia, followed by a quart of Bleach. DO NOT INHALE FUMES!!! Allow to set a minute, then slowly pull out tubing with a twisting motion , so that sock remains in hole.The sock works as a wick for the gas. Cover the entrance more thoroughly. You have killed the hogs! This is more effective if done after dark or after scaring hogs back into the hole. I only need to do this every other year.

Kknsimagineer - THANK YOU.
The war is over and I have won. Thanks to the tube & socks method but I used half gallon of each liquid. then covered the tube with soil and lots of rocks. left it in overnight with a plug in the tube and followed it up the next morning with 90 minutes of water. planted their favorite food (basil and kale) and not a nibble after two weeks.

You are most welcome. Yes these chemicals can be a dangerous combination. But using guns or propane can be as well. With a little common sense , this method of eradicating groundhogs...is the easiest and most effective method that I have found. Congratulations on your success.

Yes, dont own a gun and propane scares the daylights out of me when just an errant spark can end your day. Weeks later, not even a nibble on the tasty kale, basil and other fine plantings. Gotta cut the lawn a bit more with no more chucks but the blood pressure is way down and havent sprained an ankle bolting out of the kitchen screaming like a banshee!!!!

I know it is a very old topic but mixing bleach with ammonia is not for the faint of heart.
The most dangerous chemicals produced by mixing them are Chloramine, NH2CL and Hydrazine N2H4.
Chloramines can form chlorophenols and both are nasty chemicals.
And well, Hydrazine is not just toxic but also quite unstable.


I would mess around with a lot of chemicals on my property but not really with this particular combination.

Get assorted fruits and put them outside the hole, step back 50-100 yards and light that sucker up with whatever caliber bullet you want. (I have found .243 to be the best round for this situation)

Get a ferret they are made for ferreting out groundhogs and stand over the den with a shotgun.


Dr Qui

7 years ago

Go rent the movie Caddyshack,  Bill Murry has some interesting ideas re pest control.


i know this whole post is old as dirt, but http://www.undergroundexterm.com/groundhog_extermination.html that is pure genius.

Drop firecrackers down the hole, then finish it off with something. Seriously, drop a lot of them.

I would find a nearby fire hydrant and hook that shit up and blast them out so they are literlly flying out of the hole. Either that or use bear traps.

Is there any possibility that there are more holes that you haven't found? Perhaps some kind of secret emergency escape tunnel that they have? :D Before you do anything, I would suggest you locate all the holes. 1) Not so humane option, plug the holes, draw water from your dam to flood the tunnel network and try to drown them (or at least draw them out). 2) Another not so humane way, plug the holes, release propane / butane into the network. That could either flush them out or suffocate them. You can even light them up (optional). I don't think it will blow your dam up, but don't take my word, I've never had groundhog infested dam problem before.

Another not so humane way, plug the holes, release propane / butane into the network. That could either flush them out or suffocate them. You can even light them up (optional). I don't think it will blow your dam up, but don't take my word, I've never had groundhog infested dam problem before.

If the holes are "plugged" there is a definite likelihood of there being a bit of an explosion, or a mighty big pop anyways.

post pics, i wanna see this damn dam

There is not much to see unless you are into staring at dirt walls full of holes.

o i thought it was something like cinderblocks and the groundhogs were digging under it.... just grab a pitchfork and starting jabbing at those things... or go plug up some holes and put co2 through the thing... or rebuild the thing.... or go get some mouse traps and put some peanut butter or something on them, i would think that that would work for groundhogs too

U|m, groundhogs are a wee bit bigger than your average "rat" so a rat trap would be a bit small. They do make "muskrat" traps "Conibear Traps are good for ths since you can "bridge the hole" with them, so you get them coming or going.

Well, I did some more searching and I turned up a few more things. One website said to chuck something that smells really rank into the hole. Another website said to mixing soap and ammonium pored into there burrow will flush them out.

better trap

This was invented for getting rid of Gophers, but pehaps they have one sized for your critters....or maybe they'll build a couple for you. A new market never hurts.

I was thinking more about using smell or sound to drive the groundhog out.I have heard they do not like the smell of cat liter,but it could just be a myth.

I dont know about using cat liter because I tried and it didnt work for me.

I heard dog, not cat, and it may have been moles instead of groundhogs. You could try someone's ferret...

I have a 22 ,but no rattlesnakes(I hate snakes).I do not want to use poison because the chance that one of my animals could get second hand poisoning.I like the idea of using propane, but there are just to many holes and they seem to go fairly deep. I just need the groundhog to pop its head up for three seconds so I can take a good shot.

I was thinking that because propane is heavier than air it would sink into the inner parts of its home and choke it so it has to come to the surface for air

. Good point. A little searching turns up:
  • Propane: 583.07 kg/m3
  • CO2 : 1.98 kg/m3
  • Argon: 1.784 g/L
  • Air: 1.2 kg/m3
. Figures courtesy of Wikipedia and here

. I spent 7+ years working on an LPG (ethane, propane, butane, normal gasoline) pipeline and didn't realize it was that heavy (we always used SpG related to water).

I wonder what the groundhogs would be thinking if they knew what we were all helping to plan.

. BTW, the figure for air is dry. In the real world it will be a little higher because of water vapor.

Allow the ground hog to go into the hole. Then hook a propane tank to a hose and stick the hose in the hole. Let the gas out and have someone by each hole with a gun or bow. If it dosent come out and you are a nuts person then light the propane and blow them to kingdom come. ( I would try that last one if I were you because you would probably kill yourself :p )

. Hmmmmm. Good idea, but I think I would substitute CO2, Argon, or other inert gas (you can get them at just about any welding supply store) for the propane. I'd be afraid that an explosion would weaken the dam.

It would be a bit frightening if the propane exploded! I just know that it worked when I tried it, oh and so did an M-80 but that was just in the ground not in the dam.

I have heard stories of flamethrowers, fire, and other idiotic ideas. I think it is best to call a professional.

, Just talked to a friend that has a small earthen dam, but I'm not sure either of his recommendations are what you're looking for. 1) A .22 caliber rifle 2) Rattlesnakes . Evidently, he's used both methods to get rid of nutras in his dam, but he lives in the rural South. ;) . He also said that if groundhogs are a protected species in your area then you are, uh, fornicated (not exactly the word he used).

. If you can't/won't use poison, you need to call a pro to trap them. You're right, you need to get rid of them ASAP. . It might run them off if you keep messing with them, but it may just make them burrow deeper. . I've heard you can flood them out, but I don't think mud makes a very good dam.