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bract milkweed, short-crowned milkweed, shortcrown milkweed

asclépiade pourpreé, purple milkweed

Habit Herbs. Herbs.
Stems

4–25, erect, unbranched or branched near base, 20–40 cm, tomentulose, not glaucous, rhizomes absent.

1, erect, unbranched, 50–120 cm, puberulent in lines with curved trichomes, not glaucous, rhizomatous.

Leaves

opposite to subopposite, petiolate, with 1 or 2 stipular colleters on each side of petiole;

petiole 2–8 mm, tomentulose;

blade linear-lanceolate, 5–15 × 0.3–1.3 cm, chartaceous, base cuneate to rounded, margins often obscurely crisped, apex acute, mucronate, venation brochidodromous, surfaces tomentulose to glabrate, midvein puberulent with curved trichomes, margins minutely ciliate, laminar colleters absent.

opposite (rarely whorled at 1 midstem node), petiolate, with 1 or 2 stipular colleters on each side of petiole, also in axil;

petiole 4–18 mm, puberulent with curved trichomes;

blade ovate or oval to lanceolate or elliptic, 6–20 × 2–10 cm, chartaceous, base cuneate, margins entire, apex obtuse to acute, apiculate, or mucronate, venation eucamptodromous to faintly brochidodromous, surfaces pilosulous, sparsely so adaxially, margins ciliate, 12–20 laminar colleters.

Inflorescences

extra-axillary, pedunculate, 4–15-flowered;

peduncle 0.2–1.5 cm, tomentose, with 1 caducous bract at the base of each pedicel.

terminal, branched, also usually extra-axillary, sessile or pedunculate, 17–72-flowered;

peduncle 0–7 cm, puberulent with curved trichomes to pilosulous, with 1 caducous bract at the base of each pedicel.

Pedicels

9–15 mm, tomentose.

12–28 mm, puberulent with curved trichomes.

Flowers

erect;

calyx lobes ovate-lanceolate, 2–3 mm, apex acute, tomentulose;

corolla red-violet, sometimes green with red tinge, lobes reflexed, ovate, 4–6 mm, apex acute, minutely pilosulous;

gynostegium subsessile;

fused anthers brown, cylindric, 2–2.5 mm, wings right-triangular, closed, apical appendages ovate;

corona segments red-violet to pink basally, white apically, sessile, tubular, 1.5–2 mm, greatly exceeded by style apex, apex truncate, oblique, with a proximal tooth on each side, glabrous, internal appendage lingulate, slightly exserted, sharply inflexed towards gynostegium, glabrous;

style apex shallowly depressed, red-violet.

erect to spreading;

calyx lobes lanceolate, 3–5 mm, apex acute, puberulent with curved trichomes;

corolla reddish purple, lobes reflexed with spreading tips, elliptic, 7–10 mm, apex acute, glabrous abaxially, papillose at base adaxially;

gynostegial column 1–1.5 mm;

fused anthers brown, cylindric, 2–2.5 mm, wings broadly right-triangular, closed to slightly open at tip, apical appendages ovate;

corona segments reddish purple, stipitate, conduplicate with a lateral flange on each side, 5–6 mm, greatly exceeding style apex, apex acute, glabrous, internal appendage falcate, exserted, sharply inflexed over style apex, glabrous;

style apex shallowly depressed, red-violet to green.

Seeds

oval to ovate, 6–7 × 4–6 mm, margin winged, faces papillate-tomentulose with dendritic scales;

coma 2–2.5 cm.

ovate, 7–8 × 4–5 mm, margin winged, faces rugulose;

coma 3–4 cm.

Follicles

erect on upcurved pedicels, lance-ovoid, 5–7 × 1.2–1.8 cm, apex acuminate, shallowly ribbed, conspicuously striate, tomentulose.

erect on upcurved pedicels, lance-ovoid, 10–16 × 1.5–2.5 cm, apex long-acuminate, smooth, puberulent with curved trichomes.

Asclepias brachystephana

Asclepias purpurascens

Phenology Flowering Apr–Sep(–Oct); fruiting (May–)Jun–Oct. Flowering May–Jul(–Sep); fruiting Jul–Oct.
Habitat Plains, bajadas, pastures, arroyos, stream banks, ripar­ian areas, limestone, igneous substrates, alluvium, gravel, clay, silty, and sandy soils, desert grasslands, desert scrub, oak-juniper, juniper, and mesquite woodlands. Slopes, ravines, fields, ditches, glades, pond and lake edges, streamsides, limestone, silty, sandy, and rocky soils, oak and riparian woods, oak-hickory and mixed-hardwood forests and edges, prairie openings.
Elevation 900–1900 m. (3000–6200 ft.) 50–400 m. (200–1300 ft.)
Distribution
from FNA
AZ; NM; TX; Mexico (Aguascalientes, Chihuahua, Coahuila, Durango, Nuevo León, Sonora, Zacatecas)
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; CT; DC; DE; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MN; MO; MS; NC; NE; NH; NJ; NY; OH; OK; PA; RI; SD; TN; TX; VA; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Asclepias brachystephana is a blue-gray, bushy herb with ascending foliage, few-flowered umbels of small, red and white flowers, and conspicuously striped follicles. It is unlike any other milkweed. Nonetheless, herbarium specimens are commonly confused with those of A. asperula because the herbage of A. brachystephana turns green on drying, and the leaves of A. asperula subsp. asperula are often of similar size and shape. However, leaf arrangement in A. asperula is alternate rather than opposite. The flowers of A. brachystephana are remarkably similar to, and convergent with, those of A. cutleri, A. eastwoodiana, A. ruthiae, A. sanjuanensis, and A. uncialis (M. Fishbein et al. 2011). In Arizona, A. brachystephana is restricted to the portion of the southeastern corner of the state with Chihuahuan floristic affinities, in Cochise, Graham, Pima, and Santa Cruz counties.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Asclepias purpurascens is most common in rocky uplands of the Ozark Mountains and the piedmont of the northern Appalachian Mountains. Its reddish purple flowers are extremely showy and the species merits cultivation. The flowers have a strong cinnamon scent. Similarities to A. variegata and A. exaltata are discussed under those species. Although widespread in eastern North America, A. purpurascens is now rare over most of its range and has experienced a significant loss of populations and habitat everywhere but the Ozarks. It is considered to be of conservation concern in Connecticut, Delaware, Georgia (Floyd and Murray counties), Louisiana (Caldwell and Lincoln parishes), Maryland, Massachusetts, Michigan, Mississippi (Grenada and Washington counties), Nebraska (Nemaha and Richardson counties), New York, North Carolina, Tennessee, Virginia, and Ontario (Chatham-Kent, Essex, and Lambton counties). Moreover, it is presumed extirpated from the District of Columbia, Minnesota, New Hampshire, and Rhode Island. It has been reported, but not verified, from Maine and Vermont and, if historically present, is now extirpated there as well. Hybrids with A. amplexicaulis, A. exaltata, and A. syriaca have been documented from the New England and mid-Atlantic regions where A. purpurascens is now rare or extirpated. Putative hybrids exhibit intermediate floral and vegetative characteristics.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 14. FNA vol. 14.
Parent taxa Apocynaceae > Asclepias Apocynaceae > Asclepias
Sibling taxa
A. albicans, A. amplexicaulis, A. angustifolia, A. arenaria, A. asperula, A. californica, A. cinerea, A. connivens, A. cordifolia, A. cryptoceras, A. curassavica, A. curtissii, A. cutleri, A. eastwoodiana, A. elata, A. emoryi, A. engelmanniana, A. eriocarpa, A. erosa, A. exaltata, A. fascicularis, A. feayi, A. hallii, A. hirtella, A. humistrata, A. hypoleuca, A. incarnata, A. involucrata, A. labriformis, A. lanceolata, A. lanuginosa, A. latifolia, A. lemmonii, A. linaria, A. linearis, A. longifolia, A. macrosperma, A. macrotis, A. meadii, A. michauxii, A. nummularia, A. nyctaginifolia, A. obovata, A. oenotheroides, A. ovalifolia, A. pedicellata, A. perennis, A. prostrata, A. pumila, A. purpurascens, A. quadrifolia, A. quinquedentata, A. rubra, A. rusbyi, A. ruthiae, A. sanjuanensis, A. scaposa, A. solanoana, A. speciosa, A. sperryi, A. stenophylla, A. subulata, A. subverticillata, A. sullivantii, A. syriaca, A. texana, A. tomentosa, A. tuberosa, A. uncialis, A. variegata, A. verticillata, A. vestita, A. viridiflora, A. viridis, A. viridula, A. welshii
A. albicans, A. amplexicaulis, A. angustifolia, A. arenaria, A. asperula, A. brachystephana, A. californica, A. cinerea, A. connivens, A. cordifolia, A. cryptoceras, A. curassavica, A. curtissii, A. cutleri, A. eastwoodiana, A. elata, A. emoryi, A. engelmanniana, A. eriocarpa, A. erosa, A. exaltata, A. fascicularis, A. feayi, A. hallii, A. hirtella, A. humistrata, A. hypoleuca, A. incarnata, A. involucrata, A. labriformis, A. lanceolata, A. lanuginosa, A. latifolia, A. lemmonii, A. linaria, A. linearis, A. longifolia, A. macrosperma, A. macrotis, A. meadii, A. michauxii, A. nummularia, A. nyctaginifolia, A. obovata, A. oenotheroides, A. ovalifolia, A. pedicellata, A. perennis, A. prostrata, A. pumila, A. quadrifolia, A. quinquedentata, A. rubra, A. rusbyi, A. ruthiae, A. sanjuanensis, A. scaposa, A. solanoana, A. speciosa, A. sperryi, A. stenophylla, A. subulata, A. subverticillata, A. sullivantii, A. syriaca, A. texana, A. tomentosa, A. tuberosa, A. uncialis, A. variegata, A. verticillata, A. vestita, A. viridiflora, A. viridis, A. viridula, A. welshii
Name authority Engelmann ex Torrey in W. H. Emory: Rep. U.S. Mex. Bound. 2(1): 163. (1859) Linnaeus: Sp. Pl. 1: 214. (1753)
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