Deer are primarily browsers, meaning their diet consists largely of the leaves, buds, and tender shoots of woody plants, collectively known as browse. They actively seek out this vegetation, making trees and shrubs a regular part of their feeding habits. This behavior often results in significant damage to ornamental and young trees, especially where natural habitats overlap with residential landscapes. Deer are motivated by the need for high-protein sustenance, and landscape plants present a readily available food source.
Preferred Tree Species and Seasonal Changes
Deer exhibit clear preferences, often targeting species with high nutritional content or palatability, such as fruit trees, sugar maples, and certain evergreens like arborvitae and yew. They especially favor the tender tips and buds of young trees, where nutrients are concentrated. These preferences change significantly with the seasons as food availability fluctuates.
In spring and summer, deer prefer easily digestible, high-protein forage, focusing on new leafy growth, soft shoots, and forbs. As winter approaches and deciduous leaves drop, their diet transitions to woody browse, twigs, and buds to meet energy needs. During this dormant season, evergreens, such as white cedar and hemlock, become a food source when other vegetation is scarce. This seasonal shift means plants ignored most of the year can become attractive targets during cold weather or deep snow cover.
How to Identify Deer Damage
Identifying the culprit behind tree damage is straightforward by observing the feeding pattern, which results from deer anatomy. Deer lack upper incisors, possessing only a dental pad. This prevents them from making clean cuts when they feed. Instead, they grasp the foliage or twig between their lower teeth and the upper pad, ripping and tearing the material away.
This method of feeding leaves behind a characteristic pattern of ragged, shredded, or jagged edges on damaged leaves and stems. This contrasts with the clean, sharp, 45-degree cuts left by smaller animals like rabbits or rodents. Another indicator is the height of the damage, which rarely exceeds the deer’s maximum reach. This typically forms a discernible horizontal line on shrubs and trees, known as a browse line, usually around six feet high.
Naturally Resistant Trees and Shrubs
One strategy for reducing damage is selecting plants that deer naturally avoid due to their inherent characteristics. Deer generally shun plants with a strong, aromatic scent, a sticky or rough texture, or those containing bitter or mildly toxic compounds. Examples of resistant species include boxwood, which has an unpleasant taste, and spruces and pines, which possess strong-smelling needles and thick sap.
Shrubs with spiny or fuzzy foliage, such as hollies and juniper varieties, are also less appealing to deer. While these plants are labeled “resistant,” it is important to remember that no plant is truly deer-proof, especially during periods of high deer population density or extreme winter starvation. A hungry deer will often consume even the least palatable plants if no other food sources are available.
Methods for Tree Protection
The most effective protection against deer involves combining physical barriers with chemical deterrents. The standard for physical exclusion is a permanent fence at least eight feet tall, as deer can clear lower obstacles. For individual, high-value trees, temporary enclosures like wire mesh cages or plastic tree guards can prevent browsing damage and trunk injury from bucks rubbing their antlers.
Chemical repellents offer a practical alternative where fencing is not feasible and are categorized as either taste-based or scent-based. Taste-based products, often containing ingredients like rotten eggs or bitter agents, are applied directly to the foliage and deter deer only after they take a bite. Scent-based repellents use odors like predator urine or garlic to discourage deer from approaching the area and are sprayed around the perimeter. Both types require frequent reapplication, especially after rain or to protect new growth, and should be applied up to six feet above the anticipated snow line.