Groundhogs, also known as woodchucks, are often seen gnawing on wooden structures. This leads to a misconception that they eat wood. However, groundhogs do not consume wood for nutrition. Their interaction with wood stems from other biological needs, which can damage human property.
What Groundhogs Truly Eat
Groundhogs are primarily herbivorous, eating mostly plant matter. They are opportunistic foragers, consuming a wide variety of greens, vegetables, fruits, and grasses available in their habitat. Common food sources include clover, alfalfa, dandelions, and wild grasses. They also eat agricultural crops like lettuce, corn, peas, beans, carrots, and squash, which can lead to conflicts with gardeners and farmers.
While predominantly plant-based, groundhogs are not exclusively herbivorous. They occasionally supplement their diet with small invertebrates like grubs, grasshoppers, snails, and bird eggs. Groundhogs obtain most liquids from the juicy plants they eat, often aided by dew or rain on the leaves, rather than directly drinking water. An adult groundhog can consume over a pound of vegetation daily, building fat reserves for winter hibernation.
Why Groundhogs Gnaw on Wood
Groundhogs gnaw on wood for dental maintenance, not consumption. Like other rodents, their incisors grow continuously. These teeth can grow at about 1/16 of an inch per week. To prevent them from becoming too long and impeding their ability to eat, groundhogs must constantly wear them down.
This wearing-down process is achieved by gnawing on hard surfaces like wood, roots, and underground cables. Gnawing keeps their incisors sharp and at a functional length. If their teeth become misaligned or they do not gnaw enough, they can overgrow, making it difficult or impossible to feed, which can be life-threatening. This gnawing is an instinctive action tied to their dental health.
Impact of Groundhog Activity on Structures
Despite not eating wood, groundhogs can cause significant damage to structures through gnawing and extensive burrowing. Their powerful incisors, used for dental health, chew on wooden elements like decks, sheds, fences, and tree trunks. This gnawing can weaken structural components and create unsightly marks on property.
Beyond gnawing, their elaborate tunnel systems pose a substantial threat. Burrows can extend up to 100 feet long and reach depths of 3 to 6 feet, often with multiple entrances and chambers. Near foundations of houses, sheds, or decks, they can undermine soil stability. This can disrupt natural water flow, leading to drainage issues and soil erosion beneath the structure, potentially causing foundation settlement or failure. Large holes created by their burrowing also present tripping hazards for people and pets.