Asclepias speciosa
Asclepias speciosa
Asclepias speciosa, rarely also called Beautiful Milkweed is a plant of the genus milkweed ( Asclepias ) from the subfamily of milkweed plants ( Asclepiadoideae ).
- 4.1 Literature
- 4.2 Notes and references
Description
Vegetative characteristics
Asclepias speciosa grows as a perennial herbaceous plant, reaching heights of growth from 60 to 100 centimeters. The aboveground plant parts are hairy ( trichomes ). The ascending to erect, solid, unbranched stems are generally dense, white, woolly hairs until fluffy.
The leaves are arranged opposite constantly on the stem. The short petioles are 0.5 to 1.5 cm long. The simple leaf blade with a length of 6 to 20 cm and a width of 3 to 14 cm, elliptic to ovate or oblong - ovate to ovate - lanceolate with very broadly rounded and sometimes slightly heart-shaped Spreitenbasis and usually broadly oval - rounded, rarely acute end. The fixed - membranous leaf blades are at the bottom densely white, downy and hairy bald on the top.
Generative features
The flowering period runs from May well into September. The few to many flowers are borne in a doldigen inflorescence is pendent and separately formed on some of the top nodes present. The strong inflorescence stem is 1-10 cm long and densely white, hairy fluffy. The flower stems have a length of 2 to 3 cm.
The relatively large, showy flowers are hermaphroditic, radial symmetry and fünfzählig. The flower colors range from light purple to pink. The five white, fluffy hairy sepals are lance-shaped with a length of 5 to 6 mm. The five paddle-shaped and widely recurved petals are 10-15 mm long. The Gynostegium has a bright - pink to almost whitish, short stalk, which is only about 1 mm long and 3 mm thick. The staminal corona lobes are 10 to 14 mm is relatively long, lance-shaped and spread wide. The edges are bent upward at the base nearly tubular and decreasing towards the tip. The interstaminalen corona lobes are horn- or sickle-shaped and sharply bent inwards and significantly shorter than the staminal corona lobes. The stylus head is blunted conical, about 3 mm high and 4.5 mm thick.
The upright to downward bent stems follicles are thick to slender spindle- shaped and abruptly or more gradually tapered wedge-shaped with a length of 11-13 cm and a diameter of 2 to 3 cm. The outside is smooth to densely covered with fine spines and fine, white, hairy fluffy. The oval with a length of 6 to 9 mm seeds have a 3 to 4 cm long, white hair.
Occurrence
The distribution area of Asclepias speciosa ranges from British Columbia to the central Canada and California and Texas. Asclepias speciosa occurs on mountain meadows, open woods and along rivers, and in cultivated land. It grows widely on roadsides and along the railway lines. Asclepias speciosa grows at altitudes 1500-2600 meters.
System
The first description of Asclepias speciosa was made in 1827 by John Torrey in Annals of the Lyceum of Natural History of New York, 2, pp. 218-219. Speciosa synonyms for Asclepias Torr. are: Asclepias douglasii Hook. and Asclepias giffordii Eastw ..