Psoralea esculenta

Psoralea esculenta
Photo of Prairie Turnip taken at the McKnight Prairie near Northfield, MN. Photo by John McDaris.
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Fabales
Family:	Fabaceae
Genus:	Psoralea
Species:	P. esculenta
Binomial name
Psoralea esculenta Pursh
Synonyms
Pediomelum esculentum, Timpsula

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. English names for the plant include tipsin, teepsenee, breadroot, breadroot scurf pea, pomme blanche, and prairie turnip. The Lakota name for the plant is Timpsula.
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.
The plant grows from one or more sturdy brown roots which form rounded tuberous bodies about 7 to 10 cm below the surface, each 4 to 10 cm long. These can be eaten raw, dried, or cooked. The raw root is moderately sweet and tastes like the turnip. The dried root can be ground into a flour.
Abundant, palatable, and nutritious, the root was once a wild-gathered staple of Native Americans and early European explorers. Its characteristics make it an obvious candidate for possible domestication.