Showy native legume with long racemes of 1" indigo-blue flowers and grey-green foliage. Forms large clumps, tolerates dry conditions. Used as a purgative and emetic, as well as for toothache. Leaves yield a blue dye. The leaves are somewhat toxic and shouldn't be ingested. The upside to this is that deer leave them alone. Host plant for the Wild Indigo Duskywing butterfly. Prefers slightly acidic soil. Native to central and eastern U.S.