Arborvitae are a common landscape choice, cherished for their dense, year-round green foliage and use in privacy screens. Unfortunately, they are a primary target for white-tailed deer, especially during late fall and winter when other food sources are scarce or covered by snow. Deer browsing on the lower branches can cause significant aesthetic and structural harm, potentially ruining the plant’s shape permanently. Protecting these vulnerable plants requires a practical strategy combining physical exclusion and sensory deterrents.
Barrier Methods: Physical Protection Strategies
Physical barriers provide the most reliable method for preventing deer damage because they completely exclude the animal from accessing the foliage. The effectiveness of a perimeter fence is determined by its height, which must be at least eight feet to prevent deer from leaping over it. A fence height of seven feet may deter a calm deer, but eight feet is recommended for reliable exclusion in areas with higher deer pressure.
The material used for fencing can vary, with black polypropylene plastic mesh being a popular, cost-effective option that is less visually intrusive than solid wire. Alternatively, metal deer fencing offers greater strength and durability, which is advisable in areas where deer may attempt to chew or push through the barrier. Regardless of the material, the fence must be secured tightly to the ground to prevent deer from crawling underneath the bottom edge.
Protecting individual or young arborvitae is best accomplished using netting or commercial tree wraps. Burlap or fine mesh netting should be wrapped loosely around the entire shrub, extending from the ground up past the height of a deer’s browsing reach. It is critical to avoid wrapping the burlap too tightly, as this can trap moisture, lead to disease, or cause branch die-off.
These physical methods are most urgent in the late fall before the first heavy snowfall, as browsing pressure peaks throughout the winter months. Securing the base of individual wraps prevents deer from using their noses to lift the barrier and access the lower branches. Once spring arrives and alternative forage becomes available, the wraps should be removed to allow the plant proper air circulation and new growth.
Repellent Solutions: Deterring Deer with Taste and Scent
Repellents work by creating an aversive experience through taste or smell, discouraging deer from feeding on the treated foliage. These commercial products are broadly categorized as contact-based (taste) or area-based (scent) formulas. Contact repellents are sprayed directly onto the arborvitae and must contain ingredients that taste foul to the deer upon consumption, such as putrescent egg solids, Thiram, or bone tar oil.
Area repellents, conversely, rely on a strong, offensive odor to deter deer before they ever approach the plant. Effective scent-based ingredients often mimic the smell of a predator or decay, which is why products containing blood meal, capsaicin, or specific sulfurous compounds are commonly used. Contact repellents tend to be more effective than area repellents, but both must be applied correctly.
A high rate of reapplication is necessary because deer quickly habituate to a single deterrent, reducing its effectiveness over time. Repellents must be reapplied every two to six weeks, and immediately following heavy rainfall or new growth flushes. It is recommended to rotate between two different repellent types or active ingredients to keep the deer from becoming accustomed to a single taste or smell.
While some homeowners use homemade methods like soap or hair bags, these are generally less reliable and effective than tested commercial formulations. Furthermore, homemade sprays containing ingredients like capsaicin or ammonia can potentially damage the foliage. For reliable, long-term protection, it is best to rely on a rotation of commercially available products, especially during the dormant season.
Assessing Damage and Promoting Recovery
After a browsing event, the first step is to assess the type and extent of the damage to determine the arborvitae’s chance of recovery. Deer browsing typically leaves the branch tips with a ragged or torn appearance due to the lack of upper incisor teeth, and this damage is usually concentrated between the ground and five or six feet up the plant. More serious injury involves “buck rub,” where a male deer scrapes its antlers against the trunk, which can cause severe, potentially fatal structural damage.
The bare inner wood of an arborvitae will not regenerate new foliage because these evergreens do not have dormant buds on old wood. If the damage consists only of browsed tips where some green growth remains, the plant can recover and fill in over several growing seasons. Completely bare branches should be pruned back to a healthy side branch or the main trunk, removing the dead wood to improve the plant’s appearance.
Pruning should be delayed until late spring or early summer, after the plant has pushed out its new growth and you can clearly distinguish the dead tissue from the live wood. Aggressive pruning into the bare wood is discouraged, as it will create a permanent void that will not fill in. After pruning, proper care, including consistent watering and a light application of a balanced, slow-release fertilizer in the spring, will help promote vigor and expedite recovery.