Sumac, a common shrub or small tree belonging to the genus Rhus, is widespread across North America, often growing in disturbed areas, roadsides, and forest edges. White-tailed deer (Odocoileus virginianus) do consume sumac, utilizing it as a secondary browse source, particularly when more palatable food options are unavailable. This consumption involves specific parts of the plant and is influenced by the time of year and local environmental conditions.
Essential Distinction: Edible vs. Toxic Sumac Varieties
Not all plants labeled as “sumac” are the same, and the distinction between varieties is significant for wildlife. Deer commonly consume non-toxic types, such as Staghorn Sumac (Rhus typhina) and Smooth Sumac (Rhus glabra). These varieties are easily identified by their erect, cone-shaped clusters of bright red, fuzzy fruits, known as drupes, which persist through the winter.
In contrast, Poison Sumac (Toxicodendron vernix) is highly toxic and contains the irritating oil, urushiol. This toxic species is a wetland plant, growing exclusively in swamps, fens, and peat bogs, unlike the upland habitat of the non-toxic varieties. White-tailed deer generally avoid the leaves of this noxious plant, though its creamy white, drooping fruit clusters are occasionally consumed.
Deer Browsing Preferences: The Reality of Sumac Consumption
Deer consume multiple parts of the non-toxic sumac plant, with consumption patterns shifting seasonally based on the plant’s growth stage. The most commonly browsed parts are the current year’s growth, including tender shoots and twigs, which deer seek out in the spring and early summer because young stems are less woody and more easily digestible. Leaves are also eaten, primarily during the late summer and fall months. However, sumac leaves contain high concentrations of tannic acids, which gives them a bitter taste. This chemical defense means sumac is a lower-preference browse, only eaten consistently when preferred forage is scarce.
The reddish fruit clusters, or drupes, are a valued food source for deer and other mammals. These persistent fruits remain attached to the plant long after the leaves have fallen, making them an available source of nutrition well into the winter. The drupes offer a concentrated source of energy, protein, and fiber that can help sustain deer during the colder months.
Contextual Factors Influencing Deer Diet
The decision by a deer to consume sumac is largely driven by environmental context and the availability of alternative food sources. Sumac’s status as a lower-preference food means that high utilization often serves as an indicator of food scarcity in the area. When preferred broadleaf plants and forbs are depleted or covered by snow, deer shift their diet to include woody browse, such as sumac twigs.
The availability of sumac throughout the winter months makes it an important fallback food, especially in regions with heavy snowfall or prolonged drought. As an erect woody plant, sumac protrudes above the snow line, offering accessible food when ground-level vegetation is buried. The fruit continues to be heavily utilized through the winter, providing necessary sustenance.
The high tannin content that makes sumac less palatable during the growing season is overcome by nutritional necessity when other options disappear. This consumption pattern highlights the opportunistic nature of deer feeding habits, where they adapt their diet based on the most accessible food available.