Poisonous Plants to Know
For those interested in foraging, finding out which wild plants are poisonous and which ones might be confused with an edible plant is important. It is recommended that you learn the poisonous ones first and then feel free to experiment with the ones that you know are edible.
In the spring when gathering wild greens, there are a few plants to be aware of. Buttercups hide among the leaves of chickweed and dandelion and are sometimes picked with them. Members of this family contain glycosides that have caused irritations among livestock. Spurges are also common in gardens and lawns. They produce a milky sap that can also be irritating. Pokeweed leaves, when eaten raw, will make you throw up, even though they are edible when cooked. Milkweed is another plant that is edible when cooked but toxic raw.
Just because a flower is beautiful and smells good, doesn't mean you can eat it. Yellow jessamine flowers are an example. Honeybees have been poisoned from foraging on the nectar of these flowers. The showy, fragrant flowers of the jimsonweed are also toxic and have poisoned children sucking their nectar.
Azaleas are in the heath family, with flowers that are also tubular and fragrant, and like the yellow jessamine, are toxic. The swamp azalea is sometimes called swamp honeysuckle, making it even more confusing.
Eating a poisonous fruit by mistake has probably happened many times to many people. Suffering from the effects of a poisonous berry is more rare. Most fruits that are poisonous are so bitter that you won't eat enough to be poisoned. This includes members of the holly family that have berries that may be red or black and are considered toxic. If you eat enough of them, they can cause vomiting, diarrhea, and even death.
Pokeberries contain poisonous seeds. While the fruit may not taste bitter, poisoning can result if the seeds are ingested. Mayapple fruits are edible, but the seeds are poisonous.
Poisonous Grape Look-Alikes
Moonseed is a vine with heart-shaped leaves that looks like a grape vine and has fruits that look like grapes. Grapes have many seeds imbedded in the flesh, whereas moonseed fruits have a single seed that is in the shape of a crescent moon, which is where it got its name. Grape vines also have tendrils that are usually forked at the tip.
Virginia creeper berries are also grape-looking in appearance. The vines, however lack tendrils and leaves are made up of five leaflets. Berries of both moonseed and Virginia creeper are poisonous and should be avoided.
Legumes are bean-like pods that are characteristic of members of the pea family. Even though some of these species are edible, others contain toxic alkaloids that can result in nervous disorders.
Lupines are common herbs that grow in the western United States and Canada. Even though some may be edible when cooked, others contain toxic alkaloids and positive identification is difficult. It is best to avoid the lupines.
Locoweeds in the western part of the U.S. have reportedly been the cause of poisoning of horses, cattle, and sheep. The word loco refers to the crazy behavior shown by the horses and cattle who ate the weed.
Precatory beans, also known as rosary peas, grow in pods similar to peas with seeds that have a glossy red coating tipped with black. Seeds contain abrin, a deadly toxin.
The nightshade family has many members, some are edible and some are poisonous. It is the family that tomatoes and peppers belong to. Ground cherries, also known as husk tomatoes, are also in this family and are edible. They can be identified by their papery husks. Although edible when ripe, unripe fruits and leaves contain solanine and other alkaloids that could be toxic.
Members of the nightshade family that have poisonous berries include:
Horse nettle has yellow-orange fruits that look like ground cherry but lack the papery husk.
Black nightshade has black berries that contain solanine, an alkaloidal glucoside.
Bittersweet nightshade has bright red berries that also contain solanine.
Datura is in the nightshade family and has seeds that, when ingested, can cause hallucinations, seizures, coma, and even death. The fruit of the jimsonweed, also called thornapple, is a prickly, egg-shaped capsule containing numerous black seeds. Leaves, roots, and seeds contain the toxic alkaloid hyoscyamine.
Some of the deadliest poisons are contained in the roots of plants. This includes the water hemlock and the poison hemlock, both members of the carrot family. Young leaves of wild carrot and poison hemlock look very similar, and they both grow in meadows and fields. Mistaking the two can be fatal.
Water hemlock and water parsnip both grow in wet areas and look very similar. Water parsnip is edible whereas water hemlock can kill you. Also growing in wet areas are members of the arum family, arrow arum and skunk cabbage, that have calcium oxalate crystals. In the woodlands, Jack-in-the-pulpit can be found. This is another member of the arum family that has calcium oxalate crystals in the roots.
In a garden or meadow, burdock and pokeweed may grow side by side. Burdock is frequently used in wild food cooking. There have been occasions when poke was used instead of burdock and resulted in violent vomiting for several days.
Members of the lily family can be toxic. This is the family that wild onions and garlic belong to. If it looks like an onion or garlic, but is lacking the smell, don't eat it. It could be death camas, which can cause vomiting and, as its name implies, can be deadly. Daylilies are also in this family and even though many people have eaten them, occasionally they have caused vomiting.