Deer consume parts of oak trees, but the extent of the damage depends on the season and the availability of other food sources. Oak trees provide sustenance throughout the year. This article details the specific parts of the oak tree deer consume, the ways they inflict damage, and effective protection strategies.
Which Parts of the Oak Tree Do Deer Eat?
Deer are highly attracted to the acorns produced by oak trees, which serve as a preferred food source, especially during the fall and early winter. Acorns are low in protein but provide a dense source of carbohydrates and fats, which deer need to build up reserves before the lean winter months. Deer generally prefer white oak acorns first because they contain lower levels of bitter-tasting tannic acid compared to red oak varieties.
The consumption of other tree parts is often driven by the seasonal availability of nutrients. In the spring and summer, deer browse on tender new growth, including buds, leaves, and small twigs, which are rich in protein and easily digestible. Young oak seedlings and saplings are particularly vulnerable because a deer can consume the entire plant, eliminating the tree’s chance of survival.
During the late fall and winter, when preferred forage is scarce, deer may resort to eating the bark of oak trees. This behavior, known as girdling, is a sign of food stress and can be fatal if the bark is removed completely around the circumference of the trunk. The bark provides a source of fiber and residual nutrients when other options are exhausted.
Assessing the Risk: When and How Deer Damage Occurs
Deer damage to oak trees occurs through two distinct mechanisms: browsing and rubbing. Browsing involves the deer eating the plant material, and it is most noticeable during the late fall and winter when other food sources are dormant or covered by snow. A hungry adult deer can consume several pounds of woody twigs and buds daily, which can significantly stunt the growth of young trees.
The second type of damage is rubbing, caused by male deer (bucks) scraping their antlers against the trunk. This behavior typically occurs from late summer through the fall as bucks remove the velvet from their antlers and mark their territory. Rubbing damages the bark and the underlying vascular tissues, the phloem and xylem, which transport water and nutrients throughout the tree. Young trees, particularly those with a trunk diameter of two to three inches, are at the highest risk of fatal damage from rubbing. While mature trees are more resilient to browsing, they can still suffer from bark damage that creates entry points for disease and insects.
Practical Strategies for Protecting Oak Trees
The most reliable method for protecting oak trees from deer damage is physical exclusion, preventing contact with vulnerable parts of the tree. For young seedlings and saplings, installing tree tubes or shelters is highly effective against both browsing and rubbing. These plastic cylinders should be at least five feet tall to ensure the terminal bud is out of reach of a browsing deer.
For individual, small trees, a wire mesh cage or metal fencing can be constructed around the trunk, secured with stakes to prevent movement. To protect a larger area or a cluster of trees, a permanent perimeter fence is the most comprehensive solution. Since deer are capable jumpers, this fencing must be at least eight feet high to be fully effective at deterring them.
Repellents offer a less permanent, short-term solution and are generally categorized as taste-based or odor-based commercial products. These sprays work by making the foliage unpalatable or by emitting a scent that deer find offensive. Repellents are not effective against antler rubbing and require frequent reapplication, especially after heavy rain or snow, to maintain their deterrent properties.