Magnolia trees are popular additions to home landscapes, valued for their large, fragrant flowers and attractive foliage. A common concern for homeowners is the potential for damage from browsing deer, especially as deer populations thrive in suburban and rural environments. This article investigates the typical interaction between deer and magnolias, provides tools to identify the cause of tree damage, and offers specific methods for protecting your magnolia investment.
How Deer Interact with Magnolia Trees
Magnolia trees are generally categorized as “least preferred” by deer due to the characteristics of their leaves and bark. Varieties like the Southern Magnolia (Magnolia grandiflora) have thick, leathery leaves, often with a waxy coating, making them physically difficult to chew. These plants also contain chemical compounds, such as terpenes, which create a strong scent and bitter taste that deer typically avoid. The Rutgers University deer resistance scale rates magnolias as “seldom severely damaged,” suggesting significant browsing is uncommon.
No plant is entirely “deer-proof,” and browsing occurs when conditions change. Deer are opportunistic feeders and will consume less desirable plants during periods of food scarcity, such as harsh winters or drought. Young trees or new, tender growth are especially susceptible because the stems and leaves are softer than mature foliage. Some varieties, like the Sweetbay Magnolia (Magnolia virginiana), may be slightly more vulnerable to browsing than others due to thinner twigs.
A separate, often more destructive, form of damage is “buck rub.” This occurs predominantly in the fall during the rutting season when male deer rub their antlers against young tree trunks to remove velvet or mark territory. This rubbing shreds the bark and breaks branches, often girdling and killing a young tree regardless of its palatability. Bark consumption, where deer strip bark off a trunk for sustenance during severe winters, is a different behavior that is also highly damaging to the tree’s vascular system.
Identifying Specific Deer Browsing Signs
Confirming deer as the source of damage is crucial, as other animals like rabbits, voles, or insects can also injure trees. Deer lack upper incisor teeth, so they must grasp and tear vegetation rather than making a clean cut. This results in a ragged, rough, or shredded appearance on the tips of browsed branches. This distinguishes deer damage from the neat, angled cuts left by rabbits or rodents.
The height of the damage is another strong indicator. Deer typically browse on branches and buds between one and six feet off the ground, creating a noticeable “browse line.” Damage below one foot is usually caused by rabbits or voles. Evidence of antler rubbing includes deep, vertical tears and shredded bark on the main trunk of young trees, often with broken branches nearby. This rubbing damage is concentrated on the lower trunk, generally up to four to six feet high.
Mitigation Strategies for Tree Protection
Protecting magnolia trees involves implementing physical and chemical barriers that target both browsing and rubbing behaviors. For young or vulnerable trees, physical barriers are the most reliable defense against both browsing and rubbing.
Physical Barriers
Tree cages constructed from wire mesh or hardware cloth can be placed around individual saplings. The mesh must be secured to the ground and extend at least four to six feet high to prevent browsing. Taller perimeter fencing, ideally eight feet high, is effective for deterring deer from an entire garden area. Specialized plastic mesh deer fencing is also an option for a less obtrusive look.
To combat antler rubbing, especially during the fall rut, wrap a rigid trunk guard or a cylinder of black plastic drain tile around the lower trunk of any tree with a diameter less than four inches. These guards should be removed in the spring to prevent moisture buildup and disease.
Repellents and Deterrents
Repellent sprays offer a second line of defense by targeting the deer’s sensitive sense of smell and taste. Commercial repellents often use putrescent egg solids or animal urine scents to signal danger or unpalatability. Homemade deterrents, such as mixtures based on garlic, hot peppers, or eggs combined with water and a sticking agent, can also be effective when applied directly to the foliage. These sprays must be reapplied regularly, especially after rain or new growth, to maintain effectiveness.
Location-based strategies can also reduce damage. Plant highly palatable plants, which deer prefer, away from the magnolias. Alternatively, use strongly scented, deer-resistant herbs like lavender or rosemary around the perimeter of the protected area. The goal is to make your magnolia trees the least attractive food source or rubbing post in the immediate environment.