The discovery of damaged plants in a garden is frustrating when the cause remains a mystery. Wildlife, ranging from small rodents to larger browsing mammals, often view cultivated areas as a readily available food source. This results in physical damage to foliage, stems, and fruits. Successfully protecting a garden depends on correctly identifying the specific animal responsible for the destruction, which is the first step toward implementing effective countermeasures.
Decoding the Damage: How to Identify the Culprit
Identifying a garden pest begins with observing the affected plants and the surrounding environment. The height of the damage provides a significant clue to the size of the animal involved. Damage occurring a foot or more above the ground suggests a taller animal, such as a deer. Destruction limited to the lower 24 inches or near the soil line is often the work of smaller mammals like rabbits or voles.
Analyzing the mechanical nature of the feeding damage offers further detail. Grazing animals with incisor teeth only on their lower jaw, such as deer, tear or yank vegetation. This leaves behind a ragged, frayed edge on the remaining stem. In contrast, animals with upper and lower incisors, like rabbits, produce a distinct, clean cut, often at a 45-degree angle.
Secondary evidence also helps narrow the list of suspects. Disturbed soil, such as small excavated areas, may indicate an animal was digging for bulbs or burying a food cache. Shallow tunnels or runways in the grass or mulch are common signs left by burrowing rodents. Tracking the time of feeding, whether damage appears overnight or during the day, helps distinguish between nocturnal visitors and diurnal foragers.
Common Mammalian Garden Pests and Their Signatures
White-tailed deer are identified by their high browsing line, which extends several feet above the ground. They consume a wide variety of plants, stripping foliage and leaving behind ragged, torn stems. Male deer also inflict damage by rubbing their antlers against the bark of young trees, which can girdle the trunk and lead to the tree’s death.
Rabbits, particularly the Eastern cottontail, focus on young seedlings, tender shoots, and the bark of woody plants during winter. Their feeding is concentrated close to the ground, rarely exceeding two feet in height, and the resulting stems have a distinct clean, angled cut. Rabbits also gnaw on bark, sometimes leaving behind parallel grooves from their front teeth on the woody material.
Voles are small, mouse-like rodents that cause damage concentrated at or below the ground line. They gnaw on the bark and roots of trees and shrubs, often completely removing a ring of bark around the stem, a process known as girdling. Their activity is indicated by shallow, above-ground runways through dense grass or mulch, and the disappearance of planted bulbs.
Squirrels, including both tree and ground species, dig numerous small holes in the soil to bury or recover nuts and seeds. They damage plants by eating ripening fruits and vegetables, often taking only a single bite before abandoning the item. Twig clipping is a common signature, where they cut off the ends of branches to access buds or nuts, leaving clean-cut twig ends scattered on the ground.
Groundhogs, or woodchucks, are bulky herbivores known for their extensive burrow systems, marked by large mounds of dirt near the entrance. These animals are generalist feeders and can quickly consume entire sections of a garden, often appearing to have “mowed down” low-growing vegetables. The presence of a large, visible burrow opening in the garden or nearby landscape indicates their presence.
Effective Strategies for Exclusion and Deterrence
Once the animal is identified, a multi-pronged approach combining physical exclusion and deterrence offers reliable long-term control. Physical barriers are effective because they prevent the animal from accessing the food source. For deer, fencing must be at least eight feet tall to prevent them from jumping over the barrier.
To exclude rabbits and groundhogs, use a fence constructed of heavy-gauge wire mesh with openings no larger than one inch. This barrier should extend at least two feet above the ground and be buried six inches deep to prevent burrowing animals from digging underneath. Hardware cloth placed beneath raised garden beds can also block voles and other burrowing rodents from below.
Deterrent methods work by making the garden environment unpleasant through taste, smell, or startling action. Taste and scent repellents, often containing active ingredients like putrescent egg solids, are applied directly to the plants and must be reapplied regularly, especially after rain. Motion-activated sprinklers or noise devices can temporarily startle many mammals, though animals may eventually become accustomed to these tactics.
Habitat modification is a strategy that reduces the garden’s appeal. Removing dense brush piles, tall weeds, and debris near the garden eliminates the protective cover that small mammals, such as voles and rabbits, use for shelter and nesting. This reduction in nearby cover makes the area less inviting and exposes the animals to natural predators.