NASHVILLE, Tenn. (WKRN) — A highly toxic plant, that can be deadly if ingested, is spreading fast around the U.S.
Poison hemlock (or Conium maculatum) is about to flower in Tennessee, according to the Tennessee Department of Agriculture, and can already be seen spreading along roadsides, fields and fence lines. Poison hemlock grows nationwide and can be spotted throughout the seasons, but its most rapid growth typically occurs between March and May.
While it was “relatively rare” 30 years ago, the poisonous plant is growing more common, The Ohio State University assistant professor Joe Boggs, told Nexstar’s WCMH.
Experts say the plant is toxic to humans and animals, adding that just touching or inhaling particles while cutting can be harmful.
Here’s everything you need to know and look for as poison hemlock begins to flower.
What is poison hemlock?
The U.S. Department of Agriculture (USDA) said poison hemlock can be found throughout the U.S. and has white flowers that grow in small clusters.
The flower reportedly begins to grow in early spring and tends to grow along fence lines, irrigation ditches and in other moist places. At full height, the plant can reach 9 feet tall.
Officials described the plant as having a “hollow stem usually marked with small purple spots” with leaves that are delicate, like parsley, and has a white taproot. Its roots are sometimes confused for wild parsnips.
If ingested, what are the symptoms?
Experts warn that all parts of poison hemlock — including the leaves, stem, fruit, and root—are poisonous, especially in the spring when the plant flowers.
According to the USDA, ingestion of the plant is “frequently fatal” for livestock. In fact, sheep can reportedly be poisoned by eating as little as three ounces of green leaves. Animals can die from respiratory paralysis in 2 to 3 hours after eating the plant.
Humans shouldn’t eat any part of the plant either. “Often, poisoning occurs after the victim confuses hemlock root with wild parsnips, hemlock leaves with parsley, or hemlock seed with anise,” the USDA explains. “Whistles made from hollow stems of poison-hemlock have caused death in children.”
The USDA said signs of poisoning include:
Nervous trembling
Lack of coordination
Dilation of pupils
Respiratory paralysis
Rapid, weak pulse
Coma
Convulsions
Bloody feces and gastrointestinal irritation
Skeletal defects in calves
The Cleveland Clinic reports that humans won’t get a rash from touching the plant, but added people with sensitive skin can develop dermatitis. In severe cases, hemlock poisonings can reportedly cause complications such as: slow heartbeat, low blood pressure, muscle paralysis and kidney failure.
How to safely remove the plant from your property
The Tennessee Department of Agriculture said residents should never mow or burn poison hemlock on their property. Instead, people should use gloves to remove the plant and consult with their local agricultural officials for safe removal options.
Officials said hand pulling may be effective for small populations of the plant and recommend bagging it before disposing to prevent seed dispersal.
Herbicides can be used for larger areas but is most effective before the plant flowers, according to the Department of Natural Resources and Parks in King County, Wash.
