By Scout Nelson
Spotted water hemlock, one of the most poisonous plants in North America, is appearing in greater numbers across North Dakota this year. Extension experts link the increase to above-normal rainfall, which has created favorable growing conditions.
Native to the state, the plant is highly toxic to humans and livestock, especially cows and horses. The main toxin, cicutoxin, is most dangerous in spring, with roots containing the highest levels. Livestock deaths can occur quickly after ingestion.
Spotted water hemlock is a short-lived perennial that spreads by both seeds and roots. It thrives in wet areas such as subirrigated meadows, roadside ditches, water drains, cattail slough edges, and creek bottoms. Overland water flow and birds can help spread its seeds.
The plant is often confused with the non-toxic water parsnip. However, there are clear differences:
- Stems: Spotted water hemlock has smooth, hollow stems with reddish-purple streaks and chambered roots; water parsnip stems are green and may be slightly hairy.
- Leaves: Spotted water hemlock has sharply toothed leaves with divided leaflets; water parsnip leaves are less serrated and usually undivided.
- Flowers: Spotted water hemlock flowers are dome-shaped, up to 6 inches wide; water parsnip flowers are flatter and smaller.
If hay containing spotted water hemlock is already harvested, experts suggest feeding it in a way that allows livestock to avoid it, such as in bale feeders or rolled out on the ground. It should not be mixed into ground rations. Animals should never be forced to eat leftover hay.
When controlling spotted water hemlock with herbicides, care must be taken to avoid harming beneficial wildflowers. Always follow label directions.
Photo Credit: gettyimages-zoomtravels
Categories: North Dakota, Harvesting, Livestock, Dairy Cattle, Weather