''Orbexilum pedunculatum'', commonly known as Sampson's snakeroot, is a species of flowering plant in the legume family. It is native primarily to the

Southeastern United States The Southeastern United States, also known as the American Southeast or simply the Southeast, is a geographical List of regions in the United States, region of the United States located in the eastern portion of the Southern United States and t ...

where it is found in prairies and savannas, often in acidic soil. It is a perennial that produces racemes of flowers in early summer. Two varieties have been named, which are sometimes considered distinct species. They are: *''Orbexilum pedunculatum'' var. ''pedunculatum'' – Native to a widespread area west of the

Blue Ridge Mountains The Blue Ridge Mountains are a Physiographic regions of the United States, physiographic province of the larger Appalachian Highlands range. The mountain range is located in the Eastern United States and extends 550 miles southwest from southern ...

. *''Orbexilum pedunculatum'' var. ''psoralioides'' – Native primarily to the

Atlantic coastal plain The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

Description

''Orbexilum pedunculatum'' is a herbaceous perennial plant with a long

taproot A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot ...

that grows to a height of . The slender stem branches occasionally and is either hairless or slightly downy and bears alternate, trifoliate leaves. The

petiole Petiole may refer to: *Petiole (botany), the stalk of a leaf, attaching the blade to the stem *Petiole (insect anatomy) In entomology, petiole is the technical term for the narrow waist of some hymenopteran insects, especially ants, bees, and ...

of each leaf is up to long and has a pair of small lanceolate stipules at its base. The leaflets are up to long and wide, ellipsoid or oblong, with entire margins and acute tips. The lateral leaflets have no stalks while the terminal leaflet has a short stalk. The leaves are a medium green and hairless on the upper surface. The

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

s grow in dense

raceme A raceme () or racemoid is an unbranched, indeterminate growth, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are ...

s in the

axil A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, fl ...

s of some of the leaves. They are supported above the foliage on long, bare peduncles and are up to long. Each individual flower is long and has the five petals arranged as is typical in the pea family. The flowers are blue-violet in bud but pale violet to white when open. They are followed by nearly circular, flat seedpods with crinkled edges, each containing a single seed.

Distribution

''Orbexilum pedunculatum'' is native to the southern and southeastern parts of the United States. It is found in Alabama, Arkansas, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Maryland, Michigan, Missouri, Mississippi, North Carolina, Ohio, Oklahoma, South Carolina, Tennessee, Texas and Virginia. It typically grows on prairies and savannas, and on well-drained, sandy soils in woodland.

Uses

This plant has traditional uses in

Cherokee The Cherokee (; , or ) people are one of the Indigenous peoples of the Southeastern Woodlands of the United States. Prior to the 18th century, they were concentrated in their homelands, in towns along river valleys of what is now southwestern ...

Native American herbal medicine; the roots are used to make a topically applied salve to help knit broken bones and as treatment for wounds, ulcers and boils; other parts of the plant are used as a tonic, to relieve indigestion, to induce sweating and to stimulate blood flow during menstruation. Not to be confused with other "snakeroot" plants such as ''

Aristolochia serpentaria ''Aristolochia serpentaria'' is a species of perennial flowering plant in the Aristolochiaceae (birthwort) family. The species is commonly known as Virginia snakeroot and is native to eastern North America, from Connecticut to southern Michigan ...

'' (contains toxic aristolochic acids; also known as Virginia snakeroot), ''

Ageratina altissima ''Ageratina altissima'', also known as white snakeroot, richweed, or white sanicle, is a poisonous perennial herb in the family Asteraceae, native to eastern and central North America. An older binomial name for this species is ''Eupatorium rugo ...

'' (contains toxic tremetol, also known as white snakeroot), ''

Actaea racemosa ''Actaea racemosa'', the black cohosh, black bugbane, black snakeroot, rattle-top, or fairy candle ( syn. ''Cimicifuga racemosa''), is a species of flowering plant of the family Ranunculaceae. It is native to eastern North America from the ext ...

'' (also known as black snakeroot and black cohosh) or ''Sanicula canadensis'' (Canadian blacksnakeroot).

References

{{Taxonbar, from=Q16986935 pedunculatum