Montrose, COLO.—This spring, the Montrose County Public Health Department urges residents to be mindful of poison-hemlock. It is in the same family as carrots and parsley, but can be fatal when eaten. If you or someone you know forages for wild plants, please be on the lookout for poison-hemlock.
Poison-hemlock leaves and roots resemble carrots but can be distinguished by looking closely. Poison-hemlock stems always have some amount of red or purple spotting on them, even when young. The roots are not orange like a carrot, but rather yellowish or dirty white in color. Also, carrot leaves and stems are somewhat hairy but not poison-hemlock, which has smooth stems and leaves. In fact, poison-hemlock leaves often look shiny, especially compared with carrot leaves. It also has a distinct unpleasant musty smell.
Poison-hemlock is acutely toxic to people and animals, with symptoms appearing 20 minutes to three hours after ingestion. All parts of the plant are poisonous and even the dead canes remain toxic for up to three years. The amount of toxin varies and tends to be higher in sunny areas. Eating the plant is the main danger, but it is also toxic to the skin and respiratory system. When digging or mowing large amounts of poison-hemlock, it is best to wear gloves and a mask or take frequent breaks to avoid becoming ill.
The typical symptoms for humans include dilation of the pupils, dizziness, and trembling followed by slowing of the heartbeat, paralysis of the central nervous system, muscle paralysis, and death due to respiratory failure. For animals, symptoms include nervous trembling, salivation, lack of coordination, pupil dilation, rapid weak pulse, respiratory paralysis, coma, and sometimes death. For both people and animals, quick treatment can reverse the harm and typically there are no noticeable aftereffects. If you suspect poisoning from this plant, call for help immediately because the toxins are fast-acting – for people, call Poison Control at 1-800-222-1222 or for animals, call your veterinarian.

Photo Credit (Hemlock: Patrick J. Alexander, hosted by the USDA-NRCS PLANTS Database), (Hemlock Root: © 2018 by College of Veterinary Medicine & Biomedical Sciences; Colorado State University)