In order to control a woodchuck under a deck/shed/porch etc, you have to determine what is legal in your state along with what you want to do.
So called Non-lethal Methods:
- Harassment can work, which is just continually back filling the hole until the animal gets tired of digging out and leaves, but it could take weeks. Hazing
- One way doors can work provided you trench screen your porch area and install a one way door over the opening. Use caution when young are present, typically prior to July. I don’t recommend the inexperienced to try one-way doors as too many things can go wrong. You were warned. To trench screen, (watch out for buried wires and pipes etc.) you need to have screening above ground attached to the porch wall (1/4 inch mesh will work, galvanized is better). Then go down two inches under the soil and make a 90 degree angle out away from the porch wall at least 18 inches. This way, when the chuck meets the wall, he wants to dig straight down to get under it. But when he does he is trying to dig through mesh which he is standing on. Of course you can bury the mesh deeper if you wish and make is larger as well.
- Trap and relocate. The problem here is even if relocation is legal in your state it has a number of problems including a. potential of spreading disease b. harm to the animal as it now has to find new food sources, avoid predators and find a home before nightfall. (not very humane). You also run the risk of sending your problem somewhere else. Young may also be abandoned. Relocation Woodchucks are not a major threat to pets or children. While they have been known to carry rabies, this is rare. In general, and under normal conditions, if you leave them alone they will leave you alone. Their digging can undermine foundations. So that always has to be considered. Forget using ultrasonic devices. There is no evidence they work. You can also trap the woodchuck and dispose of it according to state laws. Visit ICWDM and click on Guides Then Wildlife Damage Management then rodents. You can also go direct at Groundhog Control There will be plenty of information there for you to choose from to learn more about groundhog control.
Key mistakes most people make in trapping are not using enough traps and not euthanizing the animal (if legal in your state).
To learn how to euthanize a woodchuck visit Euthanasia
- Once the infestation is gone secure the deck, foundation, shed to prevent future woodchuck entry. NEVER, NEVER, NEVER secure a deck, foundation or shed etc. unless you are certain that the area is no longer being used by wildlife. Fumigants. There are fumigants available for the killing of woodchucks provided you can have access to the den and the den is away from structures. Fumigants can be very dangerous. Sulfur based ones are lit and can lead to fires. They can be purchased on local hardware stores. Photoxin is extremely toxic and requires a pesticide license. Fumigants work best when the ground is moist as it holds the gas in the tunnel better. Gas dens when you are certain the chuck is present or after sundown (chucks are diurnal). ALWAYS follow the label. The Label is the law. Buildings have burned down because people foolishly misused sulfur based fumigants. Misuse of either fumigant can also kill you or someone you love.
Fumigation has risks so it is important to do the following.
- Follow the label. The Label is the law. Not following the label means you have violated Federal EPA law and possibly put yourself and others at greater risk of injury.
- There is a fire risk with sulfur-based fumigants. It is best done after a rain as the water reduces fire hazard and the water helps fill the soil space making the smoke stay in the tunnel better.
- I prefer to use fumigants shortly after dark so that the woodchuck is most likely in the den. (They are diurnal). Doing it after you see the chuck return to the den also works. Find all the den entrances. There can be as many as three, normally within 30 feet of each other. Be prepared to close the holes as soon as you insert the lighted cartridge.
- Tape the fumigant rods to a stick. This way you can light and place farther into the tunnel. Then back fill. The stick's added distance helps prevent dirt from burying the cartridge.
- Monitor the holes for several days to see if the woodchuck survived. I have not heard of odor being a problem. Once the problem is resolved, learn how to know at Paper-hole Technique visit Prevention
Disclaimer: As with any activity, remember that animal damage control comes with its own risks and problems which can include but are not limited to legalities, health threats, and personal liabilities. Be sure to follow all state laws governing wildlife and make sure you have a thorough understanding on how to resolve the animal damage complaint. My advice is only as good as your understanding of me and my understanding of your situation. If you have any questions be sure to write back. Additional Resources (Online) "Living with Woodchucks: A Guide to Controlling and Preventing Damage to your Property" at http://www.dnr.state.mn.us/livingwith_wildlife/woodchucks/index.html "How to stop that Woodchuck that Would Chuck Wood" http://agebb.missouri.edu/hort/meg/archives/v5n4/meg3.htm