Common catsear occur in lawns, pastures, gardens, seed fields, and waste places.
The leaves of this perennial plant are of basal rosettes. The leaves are rough-hairy and lobed, or wavy-margined.
The plant is poisonous and believed to be the cause of Australian Stringhalt in horses.
Flower Seed Head:
The yellow flowers occur in heads that are one to 1.5 inches in diameter. The hollow, sparsely branched flowering stems contain a white, milky juice, and are 0.75 to two feet tall. The yellow flowers occur in heads that are one to 1.5 inches in diameter.
The fruits are long-beaked and tipped by a circle of plume-like bristles.
Common catsear comes from Europe, but is now widespread in the United States and southern Canada. Abundant in western Washington and western Oregon, one population has been reported on Washington State University campus in Pullman.