Credit: Robert H. Mohlenbrock @ USDA-NRCS PLANTS Database / USDA SCS. 1989.
Midwest wetland flora: Field office illustrated guide to plant species.
Midwest National Technical Center, Lincoln, NE.
Found in different parts of the U.S., many grow readily in disturbed soils, in waste areas and with cultivated crops.
The plant is not typically ingested unless other forage is unavailable, or the plant is incorporated into hay. Poisonings occur most commonly from first and sometimes second cuttings of hay. The toxic component is an irritant, and causes digestive tract irritation.
Toxic to Horses