Asclepias purpurascens
Asclepias purpurascens
Asclepias purpurascens is a species of the genus milkweed ( Asclepias ) from the subfamily of milkweed plants ( Asclepiadoideae ). It is native to North America.
- 3.1 Literature
- 3.2 Notes and references
Description
Vegetative characteristics
Asclepias purpurascens is a perennial herbaceous plant that reaches the plant height of 40 to 100 cm. The strong stems are hairy young initially weak and short, bald later. The milky juice is whitish. The constantly against the stem arranged leaves are 0.5 to 2.5 long stalks. The leaf blade is with a length of 6 to 18 cm and a width of 3 to 10 cm wide, elliptic to ovate -oblong or lanceolate also with a blunt or pointed end. The Spreitenbasis is rounded or angled wide and running very shortly cuneate into the petiole. They are dark green and glabrous on the upper side, light green and fluffy at the bottom.
Generative features
The doldige inflorescences are usually terminally and singly or in pairs, rarely in addition also form a few inflorescences in the upper leaf axils; they contain several to many flowers. The slim Blütenstandsschäfte are hairy about 1.5 to 9 cm long and finely tomentose. The also quite thin and finely tomentose hairy flower stems are 2.0 to 3.5 cm long. The relatively large and striking purple flowers are hermaphroditic and fünfzählig. They produce quite a lot of nectar, which contains simple sugars. The five sepals are ovate - lanceolate, 3-4 mm long and finely tomentose. The tip of the five petals are bent back and 7 to 10 mm long. The Gynostegium has a very short stem, which is tapered, 1.5 to 2 mm in length and 2.5 to 3 mm wide. The corona lobes are having a length of 6 to 7 mm oblong- elliptic and pointed. The horn-shaped projection at each corner of each half is fitting, incurved sickle-shaped and sharp and much shorter than the petals. The stylus head is tapered and cropped above. It measures 2 mm in length and 3 mm in width. In the New England states Asclepias purpurascens bloom in June and July.
The follicles appear in late summer. The fruit stand upright on down sharply bent stems. They are long with a length of 10 to 16 cm and a diameter of 1 to 2 cm spindle-shaped. Outside they are essentially glabrous or weakly hairy finely tomentose. The oval seeds are 5-6 mm long, with a shock of white hair from 3.5 to 4.5 cm in length.
Occurrence
Asclepias purpurascens is native to North America (USA and Canada). It comes in Canada before in Ontario, in the United States in the states, Arkansas, Connecticut, Delaware, District of Columbia, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New York, New Jersey, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Iceland, South Dakota, Tennessee, Texas, Virginia, West Virginia and Wisconsin. It grows in scrub, open woods, prairies and fields, even in agricultural areas and along roads and railway lines.