Dioscorea villosa

from Wikipedia, the free encyclopedia
Dioscorea villosa
Dioscorea villosa, young plant in the forest.

Dioscorea villosa ,
young plant in the forest.

Systematics
Class : Bedecktsamer (Magnoliopsida)
Monocots
Order : Yams (Dioscoreales)
Family : Yam family (Dioscoreaceae)
Genre : Yams ( Dioscorea )
Type : Dioscorea villosa
Scientific name
Dioscorea villosa
L.

Dioscorea villosa is a species of the genus Yams ( Dioscorea ). It is a climbing plant native to North Americawith heart-shaped leaves.

description

Dioscorea villosa is a very variable species that includes climbing plants from one to seven meters in height. Other characteristics, such as the position of the leaves and hairiness, are also variable.

The plants form a brown rhizome 0.5 to 1.5 centimeters in diameter underground , the internodes are not separated by a separating tissue. The rhizome can be branched or unbranched, straight or irregularly curved. The twisting stems arise from the rhizome, they are grooved lengthways or winged, mostly hairless. The leaves are alternate, almost opposite or almost whirled. Especially in shady situations, the leaves are first arranged in whorls of three to seven, then alternate further up the stem. The leaves are three to 13 centimeters long, and there is also a fluted or winged petiole three to 14 centimeters long. The width of the leaves is two to 13 centimeters. The leaf shape is heart-shaped, the leaves are frosted green or bluish. The underside of the leaves can be hairy and covered with glands.

Dioscorea villosa , blooming

The male flowers threes are in cymes together, which in turn in traubigen or branched inflorescences are summarized. The inflorescence axis 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 up to three millimeters. They contain 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 gynoeceum , the female flowers also contain six staminodes . The capsule fruits are yellowish green, oval with a size of one to 3.5 centimeters. The seeds measure five to 18 millimeters.

Distribution and locations

Dioscorea villosa is widespread in eastern North America. In the north, the species reaches the area around the Great Lakes and, with individual populations, Canada. In the east and south the coast of the Atlantic and the Gulf of Mexico is reached, Florida is only populated in the northernmost part. In the west, the boundary of the distribution area coincides roughly with the boundary between forest and prairie.

Humid locations such as the edges of swamps, watercourses and lakes, damp to dry forests and bushes, as well as stony embankments and roadsides are populated. Dioscorea villosa occurs from sea level to altitudes of 1500 meters.

use

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

Systematics

Dioscorea villosa was first published in 1753 by Carl von Linné in Species Plantarum 2, p. 1033 . The name villosa comes from 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 J.F. Gmel. , Dioscorea quaternata var. Glauca (Muhl. Ex Beck) Fernald , Dioscorea villosa var. Glabrifolia (Bartlett) W. Stone , Dioscorea villosa var. Hirticaulis (Bartlett) HEAhles . In terms of their variability, the plants show a continuous spectrum that is difficult to divide into different taxa.

Individual evidence

  1. a b c d e f Lauren Raz: Dioscoreaceae . In: Flora of North America . tape 26 . Oxford University Press, New York / Oxford, pp. 482 ( eFloras.org - 1993+).
  2. ^ Dioscorea villosa at Tropicos.org. Missouri Botanical Garden, St. Louis

Web links

Commons : Dioscorea villosa  - album with pictures, videos and audio files