Houndstongue is a biennial that grows in a leafy rosette in the first year and shoots stems and flowers in the second year. It is named for its heavy, tongue-shaped, alternate leaves that have a distinct rough, hairy feel, like a dog’s tongue.  Flowers are deep red or purple with small crystals in the center. The seeds are small disks with barbs that allow them to cling onto people and animals, which is how they are dispersed.  Houndstongue contains pyrrolizidine alkaloids that cause liver failure in horses and cattle.