Poison hemlock, poisonous to animals and man

Be alert this spring for Poison hemlock (Conium maculatum), a noxious weed poisonous to sheep, cattle, swine, horses and man.  Animals can become poisoned by eating a small amount of the plant.

Poison hemlock is common to Lewis County but not a wide spread noxious weed. Often it is associated with old farmsteads and disturbed vacant lots in urban area. The plant can reach a height of three to six feet tall and has light green foliage at flowering. Hemlock flowers in late May and June. Later the plant will die back with stalks that are straw colored and the large stems stay upright thru the winter and early spring season. Rosette plants with dark green, carrot-like foliage are often scattered at the base of the stalks. It is the lush foliage from the rosettes and the spring season that maybe most tempting for livestock to browse and become poisoned.

Poison hemlock is one of the few plants associated with human poisonings by ingesting the leaves stems or roots. All plant parts of hemlock are extremely poisonous to humans and care should be taken to identifying it from other herbs that are being prepared for culinary use.

Contact the Weed Control program (360 740 1215) for information on how to control Poison hemlock and how to distinguish it from other plants.