Poison Hemlock. Conium maculatum L.

Figure 85.—Poison hemlock (Conium maculatum)

Other Common Names

Spotted parsley, spotted cowbane, poison parsley, St.-Bennet's-herb, bad-man's-oatmeal, wode-whistle, cashes, bunk, heck-how, poison root, spotted hemlock, spotted conium, poison snakeweed, beaver poison.

Habitat And Range

This poisonous weed is occasional in waste places and along roadsides, principally in the Eastern States.


Poison hemlock is a very dangerous weed, the close resemblance of the leaves to those of parsley often causing it to be mistaken for the latter with fatal results, all parts of the plant being extremely poisonous. It has a smooth, hollow, purple-spotted stem about 2 to 6 feet in height with muchbranched, and large, parsleylike leaves. In June or July it produces showy, flat-topped clusters of small white flowers. The fruit, which ripens in August and September, is grayish green and about an eighth of an inch m length The entire plant has a disagreeable, mouselike odor which is especially noticeable when the plant is bruised.

Part Used

The fruit, collected when fully developed but still green, carefully dried and stored in tight containers to protect it from air and light. It is of no value after it has been kept more than two years. The leaves are also used to some extent.