One of our earliest spring flowers, Coltsfoot bursts through the leaf litter in March and soon covers woodsy roadside banks with sunny yellow flowers. These flowers were blooming at the end of March beside the lower parking area at Bird Park in Mount Lebanon.

Gray describes the genus and the species:

TUSSILÀGO [Tourn.] L. COLTSFOOT. Head many-flowered; ray-flowers in several rows, narrowly ligulate, pistillate, fertile; disk-flowers with undivided style, sterile. Involucre nearly simple. Receptacle flat. Achenes slender-cylindric or prismatic; pappus copious, soft, and capillary. — Low perennial, with horizontal creeping rootstocks, sending up scaly scapes in early spring, bearing a single head, and producing rounded heart-shaped angled or toothed leaves later in the season, woolly when young. Flowers yellow. (Name from tussis, a cough, for which the plant is a reputed remedy.)

T. farfara L. — Wet places and along brooks, e. Que. to Pa., O.,and Minn. (Nat. from Eu.)

Another picture, and more description, is here.