Toxic Weed: Hemlock (Conium maculatum)
Posted: May 8, 2012
Grows wild along roadsides and open uncultivated areas throughout North America.
Hemlock leaves, stems and seeds contain several potent neurotoxins that affect both the central and peripheral nervous systems. Four to five pounds is a lethal dose for a horse. Most animals will avoid the plant.
Signs appear within an hour or two of consumption, starting with nervousness, tremors and incoordination, progressing to depression and diminished heart and respiratory rates and possibly colic. Death results from respiratory failure.
There is no treatment, but if smaller doses were consumed, animals may recover with supportive care.