Stems glabrous, erect, much branched, 2 to 4 feet high from a perennial root, blackening in dying. Leaves petioled, three-foliate, alternate; leaflets obovate, one-half to 1 ½ inches long, nearly sessile, blunt, tapering at the base, entire. Flowers bright yellow, rather showy, in numerous, few-flowered, terminal racemes. Each flower about one-half of an inch long; calyx campanulate, the upper two lobes united into a lobe larger than the other three; corolla consisting of a standard (upper petal), two wings (lateral petals), and a keel (two lower petals); stamens ten, distinct; fruit a short ovoid or nearly globose pod, one-fourth to one-half of an inch long, and tipped with the subulate style.
In dry or sandy soil, Maine to Vermont, Ontario, Minnesota, Florida and Louisiana. Flowering from June to September.
The Blue Wild or Blue False Indigo, Baptisia australis (Linnaeus) R. Brown, has indigo blue flowers nearly an inch long and is naturalized in eastern and southern New York from the south.
Memoir 15 N. Y. State Museum
A. Wild Indigo; Horsefly Weed - Baptisia tinctoria