We are following the treatment in Grimes, J. W. 1990. A revision of the New World species of the Psoraleeae (Leguminosae: Papilionoideae) Mem. New York Bot. Gard. 61:29. Some other treatments retain this species in Psoralea as Psoralea pedunculata (Mill.) Vail.
Psoralea pedunculata (Mill.) Vail
Hedysarum pedunculatum Mill.
Psoralea psoralioides eglandulosa (Elliott) Freeman
Common Name: Sampson's Snakeroot
Orbexilum pedunculatum is a herbaceous perennial plant growing from a spindle-shaped rootstock that can be 20mm thick; often branched at the base, the plant can grow 30 - 80cm tall.
The plant is harvested from the wild for local use as a medicine.
Although no specific mention of toxicity for this species has been found, at least some members of this genus are known to contain furanocoumarins, particularly psoralen and angelicin. These compounds can be found in low concentrations in many common foods including citrus fruirs, celery, parsley and parsnips. Ingestion or skin application of these compounds in larger quantities can cause skin photosensitization followed by hyperpigmentation[
South and eastern N. America - Kansas to Michigan, Ohio and Virginia, south to Texas and Florida
Damp or dry sandy soils in open woods, clearings and fields[
Succeeds in an ordinary garden soil[
]. Requires a well-drained soil in a sunny position[
Plants are very intolerant of root disturbance, they are best planted out into their permanent positions whilst still small[
This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby[
The roots are used as a salve on boils, sores and wounds, and also to treat broken bones[
The plant, part not specified, is diaphoretic, emmenagogue, stomachic and tonic. It is used in the treatment of obstructed menstruation, colic, indigestion, to check discharges etc[
Pre-soak the seed for 24 hours in warm water and then sow in early to mid spring in a greenhouse. Either sow the seed in individual pots or pot up the young seedlings as soon as possible in order to avoid root disturbance. Grow them on in the pots until planting out in their final positions. It is usually impossible to transplant this species without fatal damage to the root[
Division in spring. With great care since the plant resents root disturbance. It is virtually impossible to divide this species successfully[