Asclepias curassavica |
Asclepias michauxii |
|
|---|---|---|
|
blood flower, bloodflower milkweed, hierba de la cucaracha, tropical milkweed, wild ipecacuanha |
Michaux's 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. |
1–4 (rarely more), spreading to decumbent or ascending, unbranched, 15–30 cm, minutely puberulent with curved trichomes, not glaucous, rhizomes absent. |
| 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. |
opposite or alternate, sessile, often ascending and appearing secund, with 0 or 1 stipular colleter on each side of leaf base; blade narrowly linear, 4–9 × 0.1–0.4 cm, chartaceous, base cuneate, margins entire, apex acute, venation faintly eucamptodromous to obscure, surfaces glabrous, margins remotely ciliate to glabrate, 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. |
terminal, sometimes also extra-axillary at upper nodes, sessile or pedunculate, 6–28-flowered; peduncle 0–4 cm, minutely puberulent with curved trichomes, with 1 caducous bract at the base of each pedicel. |
| Pedicels | 7–20 mm, puberulent with curved trichomes. |
9–12 mm, minutely puberulent on 1 side 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, 2.5–3 mm, apex acute, sparsely puberulent with curved trichomes to glabrate; corolla green to tan, tinged pink or red, inconspicuously striate, lobes reflexed with spreading tips, elliptic, 4–5 mm, apex acute, glabrous; gynostegial column 0.5–1 mm, fused anthers green, broadly cylindric, 1.5–3 mm, wings narrowly right-triangular, open at tip, apical appendages ovate; corona segments cream, often pink-striped, to magenta, stipitate, cupulate, margins not strongly incurved, 2.5–3.5 mm, slightly exceeding style apex, apex obtuse, glabrous, internal appendage falcate, exserted, sharply inflexed over style apex, glabrous; style apex shallowly depressed, pale to deep pink. |
| Seeds | ovate, 6–7 × 4–5 mm, margin winged, faces minutely rugulose to smooth; coma 2.5–3 cm. |
ovate, 7–8 × 5–6 mm, margin winged, faces smooth; coma 1.5–2.5 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, 7.5–12.5 × 0.5–0.7 cm, apex long-attenuate, smooth, minutely puberulent with curved trichomes. |
| 2n | = 22. |
|
Asclepias curassavica |
Asclepias michauxii |
|
| Phenology | Flowering and fruiting year-round. | Flowering (Mar–)Apr–Jun(–Sep); fruiting May–Aug. |
| Habitat | Disturbed areas, fields, orchards, and gardens, canal banks, ditches, streamsides, wet prairies, marshes, swamps, coastal dunes, sandy soils. | Flats, hills, ridges, bogs, sandhills, ravines, ditches, clay, sandy, and silty soils, pine flatwoods, oak forests, savannas, wet prairies, often following fires. |
| Elevation | 0–100 m. [0–300 ft.] | 0–200 m. [0–700 ft.] |
| Distribution |
CA; FL; LA; TX; Mexico; Central America; South America; West Indies [Introduced in North America; introduced also to Old World tropics]
|
AL; FL; GA; LA; MS; SC
|
| 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 michauxii occurs with, and bears an overall similarity to, A. longifolia. They are distinguished easily in flower by the cavitate corona segments with exserted appendages of A. michauxii. Commonly, A. michauxii has decumbent stems with secund leaves, unlike A. longifolia. In fruit, A. michauxii is distinguished easily by straight pedicels. Like A. longifolia, A. michauxii barely enters Louisiana, east of the Mississippi River (Livingston, Saint Tammany, and Tangipahoa parishes), and is considered to be of conservation concern in that state. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
| Parent taxa | ||
| Sibling taxa | ||
| Name authority | Linnaeus: Sp. Pl. 1: 215. (1753) | Decaisne in A. P. de Candolle and A. L. P. P. de Candolle: Prodr. 8: 569. (1844) |
| Source | FNA vol. 14. | FNA vol. 14. |
| Web links | ||