Deer are adaptable herbivores, thriving in diverse environments from dense forests to suburban landscapes. Their diet is crucial for survival and health. As both browsers and grazers, deer consume a wide array of plant matter, adapting their feeding habits to available resources to meet nutritional needs year-round.
Main Dietary Components
Deer’s diet includes woody browse, forbs, grasses, fruits, nuts, and fungi. They primarily focus on nutritious, easily digestible options, utilizing available food sources.
Browse, the tender shoots, leaves, and twigs of woody plants, forms a substantial part of their intake. Common examples include young growth from trees and shrubs like raspberry, black cherry, grape, honeysuckle, oak, maple, willow, and birch. Forbs, non-woody, broad-leaved plants like weeds and wildflowers, are highly favored for their rich nutrient content and digestibility. Deer often seek out clover, dandelions, asters, goldenrod, pokeweed, and Virginia creeper.
Grasses are also part of their diet, though less preferred than forbs, especially mature grasses. Deer tend to consume young, tender grasses or agricultural varieties like ryegrass and timothy when available. Fruits, known as soft mast, provide essential sugars and vitamins; common choices include berries, apples, persimmons, and blackberries. Hard mast, such as acorns, hickory nuts, and chestnuts, are sought for their fat and carbohydrate content, particularly in the fall. Deer also consume fungi like mushrooms and lichens, which offer nutritional value when other food sources might be scarce.
Dietary Changes Through the Seasons
A deer’s diet changes significantly throughout the year, driven by seasonal plant availability and fluctuating nutritional requirements. During spring and early summer, deer primarily seek out fresh, green forage. This includes lush forbs, tender new leaves, and young shoots, rich in protein and easily digestible, helping them recover from winter and support antler growth in males and lactation in females.
As summer progresses, deer continue to consume green vegetation, including agricultural crops like alfalfa and soybeans, if accessible. Fall sees a shift towards high-energy foods to build fat reserves for the breeding season and winter. Acorns and other nuts become a primary food source, alongside fruits and remaining forbs.
In winter, when most vegetation is dormant or snow-covered, deer rely on woody browse, twigs, and bark. Less palatable options like white cedar, sumac, and greenbrier become crucial for survival. Their digestive system adapts to process this high-fiber diet, though nutritional stress is common during this period.
What Deer Typically Avoid
While versatile eaters, deer instinctively avoid certain plants due to unpalatable or harmful characteristics. These plants often have strong odors, bitter tastes, or unpleasant textures. Plants with a pungent scent, such as mint, lavender, rosemary, sage, thyme, and oregano, are generally bypassed. Their sensitive noses deter them from these aromatic herbs.
Plants with fuzzy, spiny, or tough leaves are also less appealing. Examples include lamb’s ear, dusty miller, astilbe, and floss flower, whose textures deer dislike. Some plants contain toxic compounds that can make deer ill, leading them to avoid species like daffodils, foxglove, monkshood, and daphne. However, if food is extremely scarce, a hungry deer might still sample plants it would normally avoid, as “deer resistant” does not mean “deer proof.”
Essential Non-Plant Nutrients
Beyond plant matter, water and specific minerals are vital for deer health and physiological functions. Water is fundamental for hydration, obtained from surface sources like streams and ponds, and from moisture within consumed vegetation. Deer require consistent water access, often seeking it from dew or directly from plants.
Minerals are crucial for bodily processes, including bone development, muscle function, and reproduction. Key macronutrients include sodium, calcium, and phosphorus. Calcium and phosphorus are important for antler growth in males and milk production in lactating females. Deer acquire these minerals from various sources, including mineral-rich soils, natural salt licks, and the plants they eat. Sodium, for example, is actively sought, especially during spring and summer, to replenish levels diluted by high moisture in lush green plants.