Homeowners and gardeners often ask if deer consume potatoes and if the tubers are safe for them. Deer have an adaptable, yet selective, herbivorous diet, which frequently leads to conflicts with cultivated crops. Understanding their natural feeding behavior and the potato plant’s chemical composition provides the answer.
The Deer’s Natural Diet
Deer are categorized as “concentrate selectors,” meaning they must consume highly digestible, nutrient-dense forage. They are ruminants with a four-chambered stomach, but their rumen is smaller than that of grazers like cattle. This physiology prevents them from efficiently processing large quantities of low-quality, fibrous material. Their diet must be rich in cell contents, such as protein, fats, and starches, which are rapidly fermented and absorbed.
Their natural diet primarily consists of browse, including the leaves, twigs, and buds of woody plants, as well as forbs (broad-leaved flowering plants). They also consume hard mast like acorns and soft mast such as berries, which provide high concentrations of energy. This highly selective browsing is aided by a narrow snout and long tongue, allowing them to precisely choose the most nutritious parts of a plant. When native food sources become scarce, especially in severe winter conditions, deer may turn toward less preferred items, including garden produce.
Attraction vs. Consumption: The Potato Preference Spectrum
Deer are not naturally drawn to the underground potato tuber, but they will consume parts of the plant and the tubers under certain circumstances. The foliage and stems, which grow above ground, are often targeted by hungry deer. This consumption is opportunistic, occurring mainly in spring when new growth is tender, or when preferred natural foods are limited.
The tubers are high in starch and carbohydrates, representing a significant energy source. They are typically safe from deer browsing because they are buried beneath the soil. Deer are not natural diggers, making the effort required to excavate a potato undesirable compared to easily accessible forage. However, deer may consume tubers if they are left lying on the ground after harvest or are easily uncovered in a garden.
Processed or cooked potatoes, which have an enhanced scent and are significantly more digestible, often become much more attractive to deer than their raw, tough-skinned counterparts. The high starch content offers a caloric reward that can override their general distaste for the raw form, especially during times of scarcity. This opportunistic consumption of exposed or readily available potatoes reflects a deer’s need for high-energy, easily obtainable food.
Toxicity Concerns: Understanding Solanine
The safety of potatoes is compromised by naturally occurring glycoalkaloids, primarily solanine, which acts as a plant defense mechanism. Potatoes belong to the nightshade family, and solanine is a neurotoxin that can cause gastrointestinal and neurological distress in mammals. Solanine concentration is not uniform throughout the plant or the tuber.
The highest concentrations are found in the leaves, stems, flowers, sprouts, and any green portions of the tuber. Exposure to light or physical damage can trigger solanine production in the potato skin, often indicated by a green tint. While small amounts of foliage may not be immediately fatal, large consumption of these high-solanine parts can lead to illness or death.
Ingestion of solanine can cause symptoms such as vomiting, diarrhea, trembling, weakness, and paralysis. Because of this inherent toxicity, especially in the green and sprouted parts of the plant, potatoes should not be intentionally offered as feed to deer or other wildlife. The risk of poisoning, combined with the fact that potatoes are not a part of their natural, balanced diet, makes them an unsafe food choice for wild deer populations.