As an avid nature lover and outdoor enthusiast, I am fascinated by deer and their behaviors. In particular, I am passionate about understanding what deer eat in order to better appreciate their place in the ecosystem. After extensive research and personal observation, I have gained deep insight into the deer diet. So, what do deer eat?

Deer are herbivores that will eat a wide variety of plants, including grasses, forbs, browse, mast, and agricultural crops. Their preferences shift with the seasons as food availability changes. Fawns initially rely on their mother’s milk before transitioning to vegetation. Overall, deer require a diverse diet of high-quality, easily digestible plants to fulfill their nutritional needs.

Now, let’s dive deeper into what deer eat!

What Do Deer Eat? The Deer Diet

Let’s take an extraordinarily in-depth look at exactly what deer eat and why they choose the foods they do.

Types of Deer Food

There are five major categories of plants that make up the majority of the deer diet:

Food Category	Description	Proportion of Diet
Grasses	Broadleaf plants like clover and alfalfa.	Less than 10%
Forbs	Leaves, shoots, and twigs of woody plants.	Up to 50%
Browse	Up to 28% in the fall	Up to 46%
Mast	Fruits, nuts, seeds, acorns.	Up to 28% in fall
Agricultural Crops	Domesticated grains and veggies.	Variable

What do deer eat? Summary table of the deer diet

More in detail, those plants and other food sources collectively make up the majority of the deer diet:

Grasses – Includes all grasses such as oats, ryegrass, bromes, wheat, and native varieties. The highest consumption is in early spring when other greens are scarce. Overall a minimal part of the diet.
Sedges & Rushes – Herbaceous plants that resemble grasses but are anatomically distinct. Often found in wetter areas. Offer an array of nourishing options during the initial days of spring.
Forbs – Herbaceous broad-leaf plants such as clovers, alfalfa, ragweed, pokeweed, dandelions, and violets. Also includes agricultural row crops. Highly palatable and nutritious.
Browse – Consists of the leaves, buds, stems, and twigs of woody browse plants including trees, shrubs, briars, vines, and some bushes.
Mast – Includes all fruits, seeds, and nuts such as acorns, hickory nuts, berries, apples, pears, and persimmons.
Mushrooms & Lichens – Fungi and lichens growing in woods and on trees. Forage of last resort but provide some protein.
Agricultural Crops – Domesticated plants like corn, soybeans, wheat, and vegetables. Offer high-quality nutrition when accessible.

Favorite Deer Foods

Deer preferences vary regionally, but some favorites include:

Favorite Specific Deer Foods by Region

While deer eat a tremendous variety of plants, there are some clear favorites based on region:

Eastern Canada

Balsam Fir
White Cedar
Willow
Dogwood
Viburnum

Northeastern United States

American Beech
Blackberry
Greenbrier
Hay-scented Fern
Sassafras

Southeastern United States

Blackgum
Grapes
Honeysuckle
Muscadine
Palmetto

Midwestern United States

Buckbrush
Canada Bluegrass
Honeysuckle
Poison Ivy
Tulip Poplar

Western United States

Buckwheat
Manzanita
Mountain Mahogany
Red Osier Dogwood
Saskatoon Serviceberry

Regional and Seasonal Variation in Food Preferences

Deer food preferences fluctuate substantially based on seasonal availability:

Spring – Forbs reach peak nutrition and digestibility. Provide protein for nursing does and antler growth. Browse consists of new shoots and leaves.
Summer – Forbs dry out so the focus turns to agricultural crops. Browse includes twigs and stems as leaves fall off.
Autumn – Hard mast-like acorns become up to 28% of the diet as deer fatten for winter. Browse remains important.
Winter – Woody browse and leftover waste grains sustain deer despite reduced nutritional needs. Emergency foods like bark are eaten.

Also, the regional habitat plays a role:

Northern Regions – More browse species like white cedar, hemlock, and birch. Acorns are less abundant.
Southern Regions – More mast species like oak, hickory, and persimmons. Softer browse plants are preferred.
Agricultural Areas – Row crops can comprise over 50% of the summer and autumn diet.
Wilderness Areas – Rely exclusively on native vegetation. Mushrooms and lichens become important.

Fawn Diet

Newborn fawns live entirely on their mother’s milk for the first month. Between 8-10 weeks, they are fully weaned off milk and transition to vegetation. Their diet mirrors adult deer but in smaller quantities.

More in detail, for the first 30 days after birth, fawns live entirely on their mother’s milk. Key facts about nursing patterns:

Nurse for short 1-2 minute sessions, several times per day
Nutrient-rich first milk (colostrum) provides antibodies
Weaning begins after 2 weeks, but continues until 8-10 weeks old
Orphaned fawns can be raised on goat milk replacer

At around 2-4 weeks old, fawns start to accompany the doe on foraging trips. They will consume small amounts of solid food, gradually increasing intake until fully weaned.

Digestion

As ruminants, deer have a four-chambered stomach specialized for digesting fibrous plant material:

Rumen – Large initial chamber where bulk fermentation takes place.
Reticulum – Area where cud is regurgitated back up for chewing.
Omasum – Absorbs nutrients from digested food particles.
Abomasum – The “true stomach”, the final stage of digestion.

Key advantages of the ruminant digestion process include:

Ability to extract nutrients from cellulose and fiber
Microbes assist in fermenting plant matter
Cud chewing enhances the breakdown of food
Able to consume large quantities quickly and continue processing later

Dietary Needs

As reported by the University Of Minnesota Extension, an average adult deer needs to consume 5-8% of its body weight in food daily. This equates to:

2-4 lbs for a 50 lb deer
5-8 lbs for a 100 lb deer
7-12 lbs for a 150 lb deer

Key nutritional needs include:

Protein – For growth and nursing, preferably 12-16% of the diet. But this can go up to 20% of their diet.
Energy – Carbohydrates needed to build fat reserves prior to winter. Also supports lactation.
Minerals – Phosphorus and calcium are required for bone and antler growth. Also, need sodium and zinc.

In autumn, deer will strive to consume as much as possible to build fat reserves. Consumption drops significantly in winter as metabolism slows and needs decline.

Preferred Food Traits

When available, deer strongly select plants exhibiting these traits:

High in essential nutrients
Very digestible and easily absorbed
Low in toxins and tannins
Palatable with a pleasant taste
Abundant and easily accessible
New growth and young shoots

The digestibility of plants decreases as they mature. New growth has more nutrients and fewer compounds that

Why Deer Prefer Different Food Types

The reasons deer favor certain food groups and plants:

Grasses

Readily abundant food source
First to sprout and go to seed
Contains sugars, starches, and some protein

Forbs

Highly digestible with soluble nutrients
Rich in proteins, boasting a remarkable content of up to 25%.
Low fiber levels enhance digestibility
Often high in minerals like phosphorus and calcium

Browse

Woody stems provide fallback food in all seasons
Evergreen shoots supply winter nutrition
High availability in forest and edge habitats
Young leaves and new growth are highly digestible

Mast

Excellent source of carbohydrates for energy storage
Acorns and nuts are high in fats and protein
Fructose in fruits aids weight gain prior to winter
Nutrients are readily obtained compared to browse

Avoiding Harmful Plants

Deer use their senses to sample and identify toxic or unpalatable plants. Indicators include:

Bitter taste
Strong odors
Coarse texture
Specialized plant defenses like thorns

There are some defenses plants employ that encourage deer to avoid eating them:

Chemical compounds – Toxins, tannins, and terpenes give an unpleasant or bitter taste.
Spines & Thorns – Physical defenses that injure or impede consumption.
Low palatability – Coarse woody stems are difficult to digest.
Camouflage – Some plants avoid being noticed through mimicry.

With experience, deer learn to associate certain smells, colors, shapes, and textures with unpleasant or toxic plants to avoid.

Methods for Finding Food

Deer rely heavily on their senses to locate optimal food sources:

Sight – Identify potential plants visually from a distance. Also, assess health and palatability.
Smell – Highly acute sense of smell detects scents up to a mile away. Smell plant chemicals.
Taste – Immediate taste response from chewing and saliva. Detect toxins.
Touch – Texture in mouth indicates quality. Softer tissues are preferable.
Memory – Recall locations of productive feeding sites from prior experience.

Impact of Deer Feeding Habits on Ecosystems

Due to their voracious browsing, deer can heavily influence the vegetation in their habitat through overgrazing. Impacts include:

Inhibiting forest regeneration by over-consuming tree saplings
Altering plant population dynamics and species diversity
Allowing invasion of exotic plants not preferred by deer
Loss of nesting habitat and food sources for other wildlife
Damage to agricultural crops and tree plantations

In the absence of predators, deer densities can increase to unhealthy levels that their habitat cannot support. Proper management of deer populations through hunting or contraception may be necessary to mitigate ecological damage.

Key Takeaways on the Deer Diet

In summary, key facts about what deer eat include:

Deer are herbivores that consume a very diverse array of plant species and vegetation.
They are highly selective browsers focused on maximizing nutrient intake.
Preferred foods are nutritious, palatable, abundant, and easily digestible.
Diet composition shifts seasonally with food availability and nutritional needs.
Grasses, forbs, browse, mast, crops, fungi, and lichens comprise the majority of their diet.
Nursing fawns get all nutrition from milk initially before transitioning to plants.
Ruminant digestion allows deer to obtain nutrients from fibrous foods.
Overbrowsing impacts plant biodiversity, regeneration, and ecosystem function.

Conclusion

After extensively researching and investigating the intricacies of the deer diet, I gained a tremendous appreciation for the remarkable complexity of how deer obtain nutrition to support growth, reproduction, and survival.

What do deer eat? While they consume a diverse array of plant foods, deer have also developed an incredible ability to seek out and identify the most palatable vegetation to optimize nutrient intake.

As an outdoor enthusiast, this knowledge will certainly enrich my future encounters with these amazing creatures.