Plant: perennial herb; stems slender, more or less erect, with secondary shoots ascending and spreading from the lower nodes, 20-60 cm tall; milky sap
Leaves: opposite, sessile or the petioles 1-2 mm long, the blades linear, 2-14 cm long, 1-5 mm broad, attenuate at apex and base
INFLORESCENCE: UMBELS 1 to several from the upper nodes, 2-5 cm broad, the peduncles 1-8 cm long.
Flowers: small; calyx lobes ca. 3 mm long; corolla purplish, the lobes 5-7 mm long; hoods erect-ascending, ovoid, 2.4-3.6 mm long along the dorsal surface, 1.2-2 mm broad at the base, about as long as the gynostegium, the rim conspicuously 5-toothed, the horns radially flat, erect, attached nearly to the top of the hoods, exserted and appearing as a sixth tooth; anther wings 1.5-1.7 mm long; corpusculum 0.5 mm long, the pollinia 0.8-1 mm long
Fruit: FOLLICLES erect on deflexed pedicels, 11-15 cm long
Misc: Open mt. woodlands with oak, ponderosa pine, and Douglas-fir, mts; 1300-2550 m (4300-8300 ft); Jul-Aug
REFERENCES: Sundell, Eric. 1994. Asclepiadaceae. J. Ariz. - Nev. Acad. Sci. Volume 27, 169-187.
Duration: Perennial
Nativity: Native
Lifeform: Forb/Herb
General: Erect or bushy from tuberous rootstalks, ranging from simple to sparingly branched, the herbage sparsely to finely pubescent, 20-60 cm tall.
Leaves: Opposite, sessile or with 1-2 mm petioles, the blades narrowly linear, 2-14 cm long, 1-5 mm wide, pointed at apex and base, minutely puberulent.
Flowers: One to several from upper nodes, 2-5 cm across, with peduncles 1-8 cm long, the flowers small, with calyx lobes about 3 mm long, the corolla is purplish with lobes 5-7 mm, the hoods are erect, involute or folded, conspicuously 5-toothed, the horns radially flat, erect, attached nearly to top of hood, exserted like a sixth tooth.
Fruits: Fusiform follicles erect on deflexed pedicels, 11-15 cm long, and less than 1 cm thick.
Ecology: Found on rocky slopes in open woodlands of oak, pine, or mixed conifer from 4,000-8,500 ft (1219-2591 m), flowers June-August.
Distribution: Reaches its northernmost limit in central Arizona then across southern New Mexico to west Texas and south to the central Mexican Highlands.
Notes: Definitely found in more mesic woodlands and forests at higher elevations. Very similar in appearance to Aslepias subverticillata when in a vegetative state, but the flowers are very different. This species has few loosely held, green, white, and purple flowers, and A. subverticillata has dense umbels of white flowers.
Ethnobotany: Unknown
Etymology: Asclepias is named for the Greek god of healing Asklepios, while quinquedentata means with or having five dentations or teeth.
Synonyms: Asclepias amsonioides, Asclepias palmeri, Asclepias quinquedentata var. neomexicana, Asclepias schaffneri
Editor: SBuckley 2011, 2014, AHazelton 2015