''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 referred to as the American Southeast or simply the Southeast, is a geographical region of the United States. It is located broadly on the eastern portion of the southern United States and the southern por ...

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 province of the larger Appalachian Mountains range. The mountain range is located in the Eastern United States, and extends 550 miles southwest from southern Pennsylvania through Maryland, West Virgin ...

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

Atlantic coastal plain The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth#Surface, Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Afr ...

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 taproo ...

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 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 An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s grow in dense

raceme A raceme ( or ) or racemoid is an unbranched, 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 produced as the s ...

s in the

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

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 (; chr, ᎠᏂᏴᏫᏯᎢ, translit=Aniyvwiyaʔi or Anigiduwagi, or chr, ᏣᎳᎩ, links=no, translit=Tsalagi) are one of the indigenous peoples of the Southeastern Woodlands of the United States. Prior to the 18th century, t ...

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 Tremetone is a chemical compound found in tremetol, a toxin mixture from snakeroot (''Ageratina altissima'') that causes milk sickness in humans and trembles in livestock. Tremetone is the main constituent of at least 11 chemically related substan ...

, 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 extrem ...

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

References

{{Taxonbar, from=Q16986935 pedunculatum