Wikipedia Article About Prairie Turnip on Wikipedia Psoralea esculenta is an herbaceous perennial plant native to prairies and dry woodlands of central North America, which bears a starchy tuberous root edible as a root vegetable. Several densely-haired stems emerge from the ground and reach up to 30 cm, bearing palmately compound leaves divided into five leaflets. Summer produces abundant blue or purple flowers in terminal clusters 5 to 10 cm long, leading to flattened, slender-tipped pods.