Groundhogs and woodchucks are the common name for the scientific name Marmota monax.  If you are having a problem with groundhogs eating your sweet potatoes or any other plant, there is a liquid that can be sprayed on the sweet potatoes that acts like a fence.  It can be purchased at your local feed and seed store and at local hardware stores.  You can also build a fence around your sweet potatoes with wire that has openings smaller than the groundhog.  The fence should be about 3 feet high and extend below the grown about 12 inches and then flair outwards about 5 inches so the groundhog cannot dig under the fence.

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