A tall, perennial herb, with resinous juice. Stem usually smooth, square, branched above, 4 to 8 feet high. Leaves opposite, ovate or deltoid-ovate, the upper ones united around the stem, the lower leaves abruptly contracted into margined petioles. Rather thin in texture, usually rough on both surfaces, the margins coarsely angulate-dentate or the tipper ones often entire, the larger leaves 6 to 12 inches long and 4 to 8 inches wide. Heads numerous, yellow, nearly flat, 2 to 3 inches broad, composed of yellow ray flowers and disk flowers, the ray flowers twenty to thirty in number, each about 1 inch long and one-sixth of an inch wide, in two or three series. Outer bracts of the involucres broadly ovate, ciliolate, foliaceous and spreading.
Memoir 15 N. Y. State Museum
Cup Plant; Indian Cup - Silphium perfoliatum
Moist soil, chiefly on prairies, southern Ontario to Minnesota and South Dakota, south to New Jersey, Georgia, Louisiana and Nebraska. Naturalized about New York City and in a few other localities in the east. Sometimes as an escape from cultivation.