_Apios tuberosa (A. Apios)_
_Flowers_--Fragrant, chocolate brown and reddish purple, numerous, about
1/2 in. long, clustered in racemes from the leaf axils. Calyx 2-lipped,
corolla papilionaceous, the broad standard petal turned backward, the
keel sickle-shaped; stamens within it 9 and 1. _Stem:_ From tuberous,
edible rootstock; climbing, slender, several feet long, the juice milky.
_Leaves:_ Compounded of 5 to 7 ovate leaflets. _Fruit:_ A leathery,
slightly curved pod, 2 to 4 in. long.
_Preferred Habitat_--Twining about undergrowth and thickets in moist or
wet ground.
_Flowering Season_--July-September.
_Distribution_--New Brunswick to Ontario, south to the Gulf states
and Kansas.