Asclepias brachystephana Engelm. ex Torr.
Family: Apocynaceae
bract milkweed,  more...
Asclepias brachystephana image

Plant: Perennial herb, 20-50 cm tall; STEMS ascending, much branched below, finely short woolly, especially on younger growth; with milky sap

Leaves: opposite, the petioles 2-8 mm long, the blades narrowly lanceolate to linear-lanceolate, 3-13 cm long, 5-20 mm broad, long attenuate to an acute apex, obtuse to acute at the base, rather persistently white woolly above, glabrate below

INFLORESCENCE: UMBELS lateral from many of the upper nodes, 2-4 cm broad, the peduncles 0.5-1.5 cm long, woolly, the pedicels white wooly

Flowers: small; calyx lobes 2-3 mm long; corolla purple, the lobes 5-6 mm long; hoods drying yellow brown, erect-ascending, hemispheric, widening upward to a truncate to 3-lobed rim, the triangular marginal lobes slightly higher than the rounded median lobe, 1.5-2.6 mm long, 1.4-2 mm broad, ca. 1-2 mm shorter than the gynostegium, the horns attached near the middle of the hoods, tangentially flat, tongue-shaped, erect, short-exserted to about the height of the marginal lobes; anther wings 1.6-1.8 mm long; corpusculum 0.2-0.3 mm long, the pollinia 1-1.1 mm long

Fruit: follicles erect on deflexed pedicels, 4-7 cm long, more or less conspicuously purple-striped

Misc: Desert mts. and plains, grasslands, roadsides; 1300-2000 m (4200-6500 ft); May-Sep

REFERENCES: Sundell, Eric. 1994. Asclepiadaceae. J. Ariz. - Nev. Acad. Sci. Volume 27, 169-187.

Sundell 1993, Woodson 1954, Kearney and Peebles 1969, McDougall 1973, Nabhan et al 2015

Duration: Perennial

Nativity: Native

Lifeform: Forb/Herb

General: Herbaceous perennials to 50 cm tall; stems clustered from rootstock, ascending, much branched below; herbage finely short-woolly, especially on younger growth; plants with milky sap.

Leaves: Opposite and petiolate, the petioles 2-8 mm long; blades narrowly lanceolate to linear-lanceolate, 3-13 cm long, 5-20 mm wide, tips long-attenuate to acute, bases obtuse to acute, surfaces rather persistently white woolly above and glabrate below, more or less conduplicate (folded lengththwise with the upper leaf surface on the inside of the fold).

Flowers: Purplish, in wooly lateral umbels 2-4 cm broad, on white-wooly peduncles,1 cm long, from many of the upper nodes; corollas purple, the lobes 5-6 mm long; hoods drying yellow brown, erect-ascending, hemispheric, widening upward to a truncate to 3-lobed rim, the triangular marginal lobes slightly higher than the rounded median lobe, 1.5-2.6 mm long, 1.4-2 mm broad, 1-2 mm shorter than the gynostegium; the horns attached near the middle of the hoods, tangentially flat, tongue-shaped, erect, short-exserted to about the height of the marginal lobes; calyx lobes 2-3 mm long.

Fruits: Follicles erect on deflexed pedicels, 4-7 cm long, more or less conspicuously purple-striped.

Ecology: Found on desert mountains, plains, mesas, grasslands, and roadsides, from 3,500-6,500 ft (1067-1981 m); flowering May-September.

Distribution: AZ, NM and w TX, south toward Guanajato through Coahuila and Sonora.

Notes: The large yellow flowers with purplish tips have stiff lobes. The flowers form large, conspicuous umbels which help to easily identify this species when in flower. Look for this species in Pima, Santa Cruz, Graham, and Cochise counties in Arizona and the southern half of New Mexico. Similar to Asclepias involucrata but that species has white-yellowish flowers and long-triangular leaves with distinctinve white-hairy margins. Toxic to livestock.

Ethnobotany: Unknown, but other species in the genus have uses.

Etymology: Asclepias is named for the Greek God of healing Asklepios; brachystepha comes from the Greek brachys, or -short,- and stephanos, meaning -crown.-

Synonyms: None

Editor: LCrumbacher 2012, SBuckley 2014, AHazelton 2015