Dioscorea villosa

Dioscorea villosa, young plant in the forest.

Dioscorea villosa is a species of the genus yams ( Dioscorea ). She is a native to North America climber with heart-shaped leaves.

Description

Dioscorea villosa is a very variable species, the climbing plants of one to seven meters Height includes. Other features, such as the leaf position and hair are variable.

The plants form a brown underground rhizome of 0.5 to 1.5 centimeters in diameter, the internodes are not issued by a separating tissue. The rhizome may be branched or unbranched, straight or irregularly curved. From the rhizome of the twining stems arise, they are longitudinally ribbed or winged, usually glabrous. The leaves are alternate, opposite or nearly approximated lively. In particular, in shady situations the leaves are first arranged in whorls of three to seven, further up the stem then another. The leaves are three to 13 centimeters long, added a gerifter or winged petiole of three to 14 centimeters in length. The width of the sheets is two to 13 centimeters. The leaf shape is heart-shaped, the leaves are frosted green or bluish. The underside of the leaves may be hairy and covered with glands.

The male flowers are in threes together in cymes, which are in turn grouped in racemose or branched inflorescences. The Blütemnstandsachse is up to 30 cm long, the branches up to 15 cm. The male flowers are greenish white, bell-shaped to tubular, with a diameter of one to two, rarely three millimeters. They have six stamens in two circles. The female inflorescences contain four to 18 flowers in a cluster. They are also greenish white, and measure two to four millimeters in diameter. In addition to the gynoecium, the female flowers also contain six staminodes. The fruit capsules are yellowish green, oval-shaped with a size of one to 3.5 centimeters. The seeds measure five to 18 millimeters.

Dissemination and locations

Dioscorea villosa is widespread in eastern North America. In the north of the kind reached the area around the Great Lakes, and to individual populations or Canada. In the east and south the coast of the Atlantic Ocean and the Gulf of Mexico is achieved, Florida is populated only in the northernmost part. In the west, the boundary of the range coincides approximately with the boundary between forest and prairie.

Are populated humid locations such as margins of swamps, streams and lakes, moist to dry woods and thickets, and rocky embankments and roadsides. Dioscorea villosa is from sea level to altitudes of 1500 meters before.

Use

Some Indians used the rhizome of Dioscorea villosa as drugs. An alcoholic extract of the rhizome was also used in the 19th century as a medicine.

System

Dioscorea villosa was first published in 1753 by Carl Linnaeus in Species Plantarum 2, p 1033. The name villosus comes from the Latin and means " shaggy, rough". Synonyms for Dioscorea villosa L. are: Dioscorea glauca Muhl. ex Beck, Dioscorea hirticaulis Bartlett, Dioscorea paniculata Michx. , Dioscorea paniculata var glabrifolia Bartlett, Dioscorea quaternata JFGmel. , Dioscorea quaternata var glauca ( Muhl. ex Beck) Fernald, Dioscorea villosa var glabrifolia ( Bartlett ) W.Stone, Dioscorea villosa var hirticaulis ( Bartlett ) HEAhles. The plants show in their variability a continuous spectrum that it is difficult to divide into different taxa.