Mouse-Ear Hawkweed

Scientific Name: Hieracium pilosella
Family Name: Asteraceae

Flower: 1 in. (2.5 cm.) wide, yellow dandelion flower, composed of all rayed petals with wavy teeth at the tips.

Leaf: 1 – 5 in. (2.5 – 12.5 cm.) green, basal leaves, hairy oblong leaves.

Plant: 3 – 12 ft. (90 – 360 cm.) tall on a leafless, hairy pink or gray stem, with one flower per stem. When the stem is broken, it exudes a milky sap.

Identifying Characteristics: Mouse-Ear Hawkweed is difficult to identify from other members of the dandelion family. Its more noticeable distinction is its flower, which is made of completely rayed petals and which only grows as one flower per stem.

Location: We found Mouse-Ear Hawkweed growing at Brandeis University in the field next to the Gosman Gym.

History and Commens: Mouse-Ear Hawkweed is native to Europe, and it was introduced into the United States in the early 1900?s, possibly from a bag of imported grass seed. It is considered a noxious weed in several states, and it has been discovered on the West Coast as well.