Colchicum autumnale is most commonly known as autumn crocus, but in various regions it is known as naked-ladies, colchicum, and meadow saffron. It should be noted that it's not a crocus, and it's not saffron, and should definitely not be used in place of saffron in cooking because eating any part of this plant can kill you.

The autumn crocus is native to Europe but has been introduced to Canada and the U.S., where it is both grown in gardens and lives as a wild escapee in meadows and woodlands. It's a perennial herb in the lily family (Liliaceae) which grows from a corm (a solid bulb) that can unfortunately be mistaken for a wild onion. The rapierlike leaves grow about a foot high, and in the early fall one or two leafless stalks sprout from the corm; each stalk produces a single white-to-purplish-pink flower that resembles a crocus.

The extreme toxicity of this plant has been known since the times of ancient Greece, but in the fifth century, herbalists in the Byzantine Empire discovered it could be used to treat rheumatism and arthritis, and the Arabs began to use it for gout. The useful active ingredient in the plant is an alkaloid called colchicine, which is still used to treat gout and which has anticancer properties.

Poisoning from this plant resembles arsenic poisoning; the symptoms (which occur 2 to 5 hours after the plant has been eaten) include burning in the mouth and throat, diarrhea, stomach pain, vomiting, and kidney failure. Death from respiratory failure often follows. Less than than two grams of the seeds is enough to kill a child; a specific antidote doesn't exist, so treatment typically involves giving the victim activated charcoal or pumping the stomach.