Some of the weirder-looking poisonous berries such as the eyeball-like white baneberries (Actaea pachypoda) found in the eastern and midwestern United States aren't likely to tempt your palate [source: USDA database 2]. But these are among the ones that resemble edible berries.
Climbing nightshade (Solanum dulcamara): There are numerous varieties of this invasive vine that grows in thickets and clearings across most of the United States and Canada [source: USDA database 3]. Its medium to dark green leaves are twin-lobed, veiny and pointed, and beneath the leaves are droopy, bright red berries that look a little like the cherry atop the pile of whipped cream on a sundae [source: Nightshade]. But don't eat this bittersweet fruit because it contains solanine and saponins, chemicals that attack the nervous and respiratory systems and can kill you [source: Couplan].
Sticky currant (Ribes Viscosissimum): This invasive weed is found in the western United States and Canada. Don't confuse it with the edible varieties of currants, because it'll make you puke. The sticky substance on the leaves, twigs and fruit are a warning sign, as are the bristly hairs that sometimes cover the fruit [source: Elias].
American pokeweed (Phytolacca Americana): Also called common pokeweed, this plant is found in most of the United States and in eastern and central Canada [source: USDA database 5]. It's found in woods, pastures and along roadsides. The pokeweed plant, which grows up to 10 feet (3 meters) in height, resembles a small tree and has dark green lance-shaped leaves that can be as much as 20 inches (50.8 centimeters) long, with white-green flowers. The berries, which are purple and black, droop like bunches of grapes. Pokewood juice once was used to improve the color of cheap wines, which may have resulted in more than a few drunks becoming violently ill. Like the rest of the plant, the berries contain poisonous oxalic acid, saporins and the alkaloid phytolaccin, which wreak gastrointestinal havoc and cause death from respiratory failure [source: Ohio State].
In addition, be careful with elderberries (Sambucus canaensis), which are found in woods and fields throughout the United States, even though the purple-black fruit, when ripe and cooked, is a safe traditional cooking ingredient in pies, pancakes, jellies and wine. The problem: Raw unripe berries -- the leaves, twigs and roots -- contain poisons like cyanogenic glycoside, which can cause nausea, vomiting and other yucky symptoms. So don't eat them off the bush [source: North Carolina State University].
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