Groundhogs chew wood and can damage wooden structures on residential properties. This gnawing behavior is driven by biological needs and their search for optimal burrow locations. Understanding the reasons for their activity and the types of damage they inflict is key to protecting property. This article explores the biological drive behind groundhog gnawing, the resulting structural issues, and practical methods for deterring their presence.
The Biological Necessity of Groundhog Gnawing
The groundhog, or woodchuck, is a rodent whose dental structure requires constant gnawing to survive. Like all rodents, they possess four chisel-shaped incisors that continuously grow throughout their lives. These teeth can grow rapidly, accumulating to over three inches of growth annually.
To counteract this growth and keep their teeth functional, groundhogs must constantly grind them down. They chew on hard, abrasive materials like tough roots, tree bark, and wood structures. This action is dental maintenance, preventing the incisors from growing so long that they impede the animal’s ability to eat.
If the upper and lower incisors do not align properly, a condition known as malocclusion can occur. Without the necessary wear, the teeth grow uncontrollably, leading to severe health issues and starvation. The groundhog’s instinct to gnaw on hard materials, including wood, is a biological requirement for its survival.
Structural Damage from Gnawing and Tunneling Proximity
Groundhog damage involves direct gnawing on wood and indirect instability caused by their burrow systems. Direct damage affects structures close to the ground, such as wooden decks, porch supports, and shed boards. They also gnaw on tree bark, particularly around the base of younger trees, which can girdle the tree and disrupt its nutrient transport system.
The primary structural threat arises from tunnels excavated near foundations and supports. A single burrow can be a complex network, sometimes extending up to 65 feet in length and reaching depths of five feet. When these subterranean systems are excavated near structures, they remove supporting soil, which can undermine stability.
Burrowing beneath concrete slabs, patios, or shed foundations can lead to cracking, sinking, or tilting of the structure. Furthermore, an entrance hole located against a foundation can funnel rainwater into the tunnel system, causing soil erosion and disrupting the water balance around the building. This water intrusion weakens the foundation and may lead to costly repairs.
Practical Methods for Deterring Groundhog Activity
Exclusion is the primary method for preventing groundhogs from accessing vulnerable areas and establishing burrows. To protect structures like sheds and decks, install a physical barrier of heavy-gauge wire mesh or hardware cloth around the perimeter. This material should extend at least 12 inches below the ground and be bent into an L-shape that flares outward for another 12 inches.
This L-shaped barrier prevents the groundhog from digging under the fence, forcing them to encounter the horizontal barrier. For gardens, a fence at least three feet high is recommended, often with the top portion bent outward to discourage climbing. Exclusion also includes sealing openings beneath porches or sheds with wire mesh.
Taste and scent deterrents can be used to make an area unappealing, but they require consistent reapplication. Repellents often use ingredients like castor oil, cayenne pepper, or strong-smelling herb blends that irritate the groundhog’s sensitive nose and eyes. Predator scents, such as fox or coyote urine, can also be sprayed to signal danger, though their effectiveness diminishes quickly.