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blood flower, bloodflower milkweed, hierba de la cucaracha, tropical milkweed, wild ipecacuanha

low milkweed, plains milkweed, plains or low or dwarf milkweed

Habit Subshrubs or herbs. Herbs.
Stems

1–several, erect, sparsely to moderately branched, 30–150 cm, minutely pilosulous in a line to glabrate, not glaucous, rhizomes absent.

1–12, erect, unbranched to moderately branched below, 10–30 cm, puberulent with curved trichomes, not glaucous, rhizomatous.

Leaves

persistent or gradually caducous from the base, opposite, petiolate, with 1 or 2 stipular colleters on each side of petiole on a ciliate interpetiolar ridge;

petiole 4–25 mm, puberulent with curved trichomes in a line to glabrate;

blade elliptic or oval to linear, 4–18 × 0.3–4.5 cm, membranous, base cuneate, margins entire, apex acute to acuminate to attenuate, venation eucamptodromous to faintly brochidodromous, surfaces sparsely puberulent with curved trichomes on veins abaxially, sparsely puberulent with curved trichomes on veins to glabrate adaxially, margins ciliate, laminar colleters absent.

alternate, sessile, with 1 stipular colleter on each side of leaf base;

blade needlelike to narrowly linear, 2.5–5.5 × 0.05–0.1 cm, chartaceous, base cuneate, margins entire, apex acute, mucronate, venation obscure, surfaces glabrous, margins ciliate, laminar colleters absent.

Inflorescences

extra-axillary, pedunculate, 5–22-flowered;

peduncle 0.5–8 cm, puberulent with curved trichomes in a line, with 1 caducous bract at the base of each pedicel.

extra-axillary at upper nodes, sometimes appearing terminal, pedunculate, 3–13-flowered;

peduncle 0.1–2 cm, puberulent with curved trichomes, with 1 caducous bract at the base of each pedicel.

Pedicels

7–20 mm, puberulent with curved trichomes.

6–16 mm, puberulent with curved trichomes.

Flowers

erect;

calyx lobes linear-lanceolate, 3–4 mm, apex acute, puberulent with curved trichomes;

corolla red, sometimes yellow in throat (to wholly orange or yellow in cultivars), lobes reflexed with spreading tips, elliptic to oval, 6–9 mm, apex acute, glabrous abaxially, minutely papillose at base adaxially;

gynostegial column 2–2.5 mm;

fused anthers yellowish green to tan, cylindric, 1.5–2 mm, wings narrowly right-triangular, closed, apical appendages deltoid;

corona segments yellow to orange, stipitate, tubular, dorsally somewhat flattened, 3.5–4 mm, exceeding style apex, apex obtuse to acute, glabrous, internal appendage falcate, exserted, arching over style apex, glabrous;

style apex shallowly depressed, yellow.

erect;

calyx lobes narrowly lanceolate, 2–3 mm, apex acute, puberulent with curved trichomes to glabrate;

corolla pink to cream with a pink tinge, lobes reflexed with spreading tips, elliptic, 3.5–4.5 mm, apex acute, glabrous abaxially, minutely papillose at base adaxially;

gynostegial column 0.8–1 mm;

fused anthers green, columnar, 1–1.5 mm, wings narrowly right-triangular, closed, apical appendages deltoid;

corona segments cream, sometimes tinged or striped pink, stipitate, tubular, dorsally flattened, 2–2.5 mm, exceeded by to equaling style apex, apex obtuse, glabrous, internal appendage acicular, exserted, arching towards style apex, glabrous;

style apex shallowly depressed, cream.

Seeds

ovate, 6–7 × 4–5 mm, margin winged, faces minutely rugulose to smooth;

coma 2.5–3 cm.

ovate, 5–6 × 3–5 mm, margin winged, faces smooth;

coma 2–3 cm.

Follicles

erect on straight pedicels, fusiform, 6–10 × 0.5–1.2 cm, apex acuminate to attenuate, smooth, glabrous.

erect on straight pedicels, narrowly fusiform, 2.5–9.5 × 0.5–1 cm, apex acuminate to attenuate, smooth, minutely puberulent with curved trichomes to glabrate.

2n

= 22.

Asclepias curassavica

Asclepias pumila

Phenology Flowering and fruiting year-round. Flowering (May–)Jun–Sep; fruiting Aug–Oct.
Habitat Disturbed areas, fields, orchards, and gardens, canal banks, ditches, streamsides, wet prairies, marshes, swamps, coastal dunes, sandy soils. Slopes, bluffs, plains, sandhills, dunes, rock outcrops, playas, ditches, basalt, alluvium, sandy, clay, rocky, and gravel soils, prairies, meadows, shrubby grasslands, pine woodlands.
Elevation 0–100 m. [0–300 ft.] 600–2300 m. [2000–7500 ft.]
Distribution
from FNA
CA; FL; LA; TX; Mexico; Central America; South America; West Indies [Introduced in North America; introduced also to Old World tropics]
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; KS; MT; ND; NE; NM; OK; SD; TX; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Asclepias curassavica is the only non-native Asclepias species naturalized in the flora area. It is very commonly cultivated, originally for its strikingly colored flowers and their attraction of Lepidoptera and Hymenoptera. Recently, they have been valued also as a host plant for monarch butterflies. Cultivars with pure orange or pure yellow flowers are readily available. The species develops rapidly from seed and can be grown as an annual (in the horticultural sense) anywhere in the region. Though often described as an annual, like all species of Asclepias, it has a perennial habit. It may persist through mild winters at least as far north as Oklahoma but has only become established in frost-free areas of the southern United States.

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

Asclepias linaria and A. pumila of southeastern Arizona and extreme southwestern New Mexico are the only milkweeds with densely spiraled, linear to needlelike leaves. Hybrids with A. subverticillata and A. verticillata have been documented; see discussion under these species. When not flowering, A. pumila is cryptic and easily overlooked in its grassland habitat, especially when growing among Bouteloua species. Specimens supposedly from Illinois and Arizona (C. Mohr [US]) undoubtedly have incorrect label data. A population in the Sacramento Mountains of southern New Mexico (Otero County) appears to be a significant southern disjunction.

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

Parent taxa Apocynaceae > Asclepias Apocynaceae > Asclepias
Sibling taxa
A. albicans, A. amplexicaulis, A. angustifolia, A. arenaria, A. asperula, A. brachystephana, A. californica, A. cinerea, A. connivens, A. cordifolia, A. cryptoceras, 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. 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
Synonyms A. verticillata var. pumila
Name authority Linnaeus: Sp. Pl. 1: 215. (1753) (A. Gray) Vail: Bull. Torrey Bot. Club 25: 175. (1898)
Source FNA vol. 14. Treatment author: Mark Fishbein. FNA vol. 14. Treatment author: Mark Fishbein.
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