Prairie Rosinweed

Rosinweed (or wholeleaf rosinweed) is a coarse, sunflower-like perennial that derives its common name from the resinous gummy sap exuded by broken/cut plant stems. It grows shorter (often to 2-3’ tall) than most of the other native silphiums, though it may grow as tall as 6’. It is native from Michigan to Wyoming south to Alabama and New Mexico. It typically occurs in rocky or dry open woods, prairies and glades. It grows on erect, hairy stems sparsely clad with pairs of rough, stalkless, bristly, hairless to woolly, toothed to toothless, medium green leaves (to 6” long). Leaves are quite variable in shape, ranging from lanceolate to ovate to elliptic. Flowers (to 2-3” diameter) resembling small sunflowers appear in corymb-like inflorescences in mid-summer. Each flower features yellow rays and a yellow center disk. Flowers are subtended by bracts with reflexed tips.