Dewberries are a type of trailing blackberry belonging to the genus Rubus, which also includes raspberries and erect blackberries. The answer to whether they are poisonous is straightforward: mature dewberries are safe for consumption. Common dewberry species, such as Rubus flagellaris and Rubus caesius, are widely gathered in the wild. Like many wild edibles, correct identification is important for safety, especially distinguishing these berries from potentially harmful look-alikes.
Safety Status and Culinary Uses
Ripe dewberries are edible and offer a sweet-tart flavor often described as richer and sweeter than some cultivated blackberries. The fruit is an aggregate of small fleshy drupelets, which turns from green to red, and finally to a deep purple-black when fully ripe. Consuming unripe berries or an excessive quantity of ripe fruit may cause minor digestive upset, such as stomach discomfort or diarrhea.
The berries are highly versatile in the kitchen, frequently used in jams, jellies, pies, and cobblers, or simply eaten raw. Beyond the fruit, other parts of the Rubus plant have historical uses. The leaves of some species are dried to make a tea traditionally used as a remedy for diarrhea, and the young shoots are occasionally peeled and eaten raw in the spring.
Key Features for Identifying Dewberries
Dewberries are categorized as low-growing, trailing woody vines, which distinguishes them from the more erect, cane-growing blackberries. Their stems can trail along the ground for up to 15 feet, are slender, and feature scattered, hooked prickles. The leaves are compound, usually consisting of three leaflets, though sometimes five leaflets can be present.
These leaflets are ovate, have serrated edges, and are typically a lighter green on the underside. The fruit is generally longer than it is wide and can reach about one inch in length. European dewberry fruit often has a noticeable blue-grey cast to its dark drupelets.
Common Toxic Berries Mistaken for Dewberries
The main concern is mistaking dewberries for other low-lying toxic berries, though few truly mimic the aggregate structure of the Rubus fruit. One potential confusion arises with Bittersweet Nightshade (Solanum dulcamara), which is a sprawling vine. Nightshade berries are simple and round, progressing from green to yellow, then orange, and finally red, a different color progression than dewberries.
Another plant sometimes confused with dewberries is Virginia Creeper (Parthenocissus quinquefolia), an aggressive vine that produces bluish-black berries. The key difference is the leaf structure, as Virginia Creeper has five leaflets radiating from a single point, whereas dewberries typically have three. Virginia Creeper fruits contain oxalate crystals, which cause immediate irritation and severe gastrointestinal distress if consumed.