A deer’s “favorite food” is not a single item, but rather a constantly shifting category of the most nutritious and palatable forage available. White-tailed and mule deer are selective herbivores known as browsers, not grazers like cattle. Their narrow muzzles and specialized digestive systems are designed to pick out the most easily digestible plant parts with the highest concentration of nutrients. This feeding strategy means deer constantly seek high-quality food sources to meet their metabolic needs, linking their preference to the immediate biological requirement for protein, energy, or fat.
The Core Diet: Browsing and Foraging
The bulk of a deer’s diet, sometimes accounting for 30 to 60% annually, consists of “browse.” Browse includes the leaves, soft shoots, and buds of woody plants like trees and shrubs. This structural vegetation is the consistent foundation of their intake, especially when more desirable foods are scarce. The deer’s four-chambered stomach, or rumen, relies on a specific microbial community to break down this fibrous material.
Deer are classified as “concentrate selectors,” meaning they prioritize easily digestible foods rich in cell contents. They select the youngest, most tender tips of branches, which have a higher concentration of digestible energy. While woody browse is less preferred than high-energy foods, it serves as a survival food during the winter months when other vegetation is dormant.
High-Value Foods: The True Favorites
Deer actively seek out foods that provide an immediate caloric or protein return, often traveling significant distances. These high-value items are the true “favorites” because they directly support reproduction and winter survival. The most significant of these sought-after foods is “mast,” which includes both hard and soft varieties.
Hard mast, like acorns and beechnuts, is a primary favorite in the fall, offering a dense source of carbohydrates and fat for building winter reserves. White oak acorns are often preferred over red oak varieties due to their lower tannin content. Soft mast includes fruits such as apples, persimmons, and berries, which are consumed for their high sugar content and easily accessible energy. Deer also heavily utilize specific agricultural crops, such as alfalfa, clover, and soybeans, because these plants offer exceptional levels of protein and digestibility.
Dietary Adaptation: Seasonal Changes
A deer’s definition of a favorite food changes dramatically based on the time of year and their current physiological demands. This adaptation links their diet directly to their metabolism and the cycle of the seasons.
In spring and early summer, the demand for protein is highest, driven by antler growth in bucks and lactation in does. During this period, their preference shifts toward high-protein forbs and legumes, which are easily digestible, herbaceous, non-woody plants. These plants can offer protein levels between 14% and 22%, necessary for rapid growth and recovery.
As late summer transitions into fall, the focus changes to energy storage in preparation for the breeding season and winter. Deer actively seek out high-carbohydrate and high-fat foods, leading to the intensive consumption of hard mast like acorns. This allows them to accumulate a layer of fat, which is the primary energy reserve for surviving the cold months.
During deep winter, deer enter a survival mode where their metabolism slows, and their gut biome adjusts to process lower-quality, high-fiber food. The preferred foods become the most readily available woody browse, such as twigs, buds, and evergreen foliage. The deer’s body is physiologically adapted to subsist on this sparse diet until spring returns.
Foods to Avoid Feeding Deer
While the impulse to feed deer is often well-intentioned, providing the wrong food can be detrimental to their health. Processed human foods, such as bread, chips, and baked goods, offer no beneficial nutrition and can cause digestive upset. The most significant danger comes from feeding deer large quantities of high-carbohydrate grains like corn or wheat, especially during winter.
The deer’s specialized rumen contains microbes adapted to the specific food they are consuming. A sudden large intake of carbohydrates can overwhelm these microbes, leading to a condition called rumen acidosis. This causes a rapid buildup of lactic acid, which lowers the pH in the stomach and destroys the microbial community. A deer can effectively starve to death with a full stomach because its digestive system cannot process food. Furthermore, artificial feeding sites cause deer to congregate, which increases the risk of disease transmission, including Chronic Wasting Disease (CWD).