Asclepias obovata |
Asclepias vestita |
|
---|---|---|
pineland milkweed |
woolly milkweed, wooly milkweed |
|
Habit | Herbs. | Herbs. |
Stems | 1 (rarely more), erect to spreading, unbranched, 40–70(–200) cm, densely hirtellous to velutinous, not glaucous, rhizomes absent. |
1–20, prostrate to decumbent or ascending, rarely branched, 25–90 cm, tomentose, not glaucous, rhizomes absent. |
Leaves | opposite, petiolate, with 1 or 2 stipular colleters on each side of petiole; petiole 1–4 mm, densely hirtellous to velutinous; blade oblong or elliptic to obovate or ovate, 4–9 × 1–3.5 cm, subcoriaceous, base rounded or truncate to cordate, margins sometimes crisped, apex acute to truncate, sometimes emarginate, often mucronate, venation brochidodromous, surfaces densely hirtellous to velutinous abaxially, hirtellous adaxially, margins ciliate, 8–12 laminar colleters. |
opposite, petiolate, with 0 or 1 stipular colleter on each side of petiole; petiole 3–10 mm, tomentose; blade elliptic or oval to lanceolate or ovate, 8–20 × 2–10 cm, chartaceous, base cuneate to rounded or cordate, margins entire, apex acute to attenuate or acuminate, mucronate, venation eucamptodromous to faintly brochidodromous, surfaces densely to thinly tomentose, laminar colleters absent. |
Inflorescences | extra-axillary, sometimes also appearing terminal, sessile or pedunculate, 7–31-flowered; peduncle 0–0.5 cm, densely hirtellous to velutinous, with 1 caducous bract at the base of each pedicel. |
extra-axillary at upper nodes, sometimes appearing terminal, sessile or pedunculate, 19–45-flowered; peduncle 0–3.5 cm, densely tomentose, with 1 caducous bract at the base of each pedicel. |
Pedicels | 10–12 mm, densely hirtellous to velutinous. |
15–35 mm, densely tomentose. |
Flowers | erect to pendent; calyx lobes elliptic, 5–6 mm, apex acute, densely hirtellous; corolla green, sometimes tinged reddish or bronze, lobes reflexed, sometimes with spreading tips, elliptic, 7–9 mm, apex acute, glabrous abaxially, minutely papillose at base adaxially; gynostegial column 1–1.5 mm; fused anthers green, obconic, 2.5–4 mm, wings right-triangular, open at base, apical appendages broadly ovate; corona segments bronze to yellow, often tinged red, sometimes apically cream or pale, stipitate, tubular, somewhat flattened laterally, flared at base, 5–8 mm, greatly exceeding style apex, apex rounded, flared, glabrous, internal appendage falcate, exserted, sharply incurved over style apex, glabrous; style apex shallowly depressed, green. |
erect to pendent; calyx lobes elliptic, 5–6 mm, apex acute, densely tomentose; corolla green to pinkish purple, lobes reflexed, sometimes with spreading tips, oval, 6–9 mm, apex acute, densely tomentose abaxially, papillose at base adaxially; gynostegial column 1–1.5 mm; fused anthers dark brown, truncately obconic, 1.5–2 mm, wings right-triangular, closed, apical appendages ovate; corona segments cream to dark pink, sessile, conduplicate, dorsally rounded, 3–3.5 mm, equaling or slightly exceeding style apex, apex obtuse, oblique, margin with proximal tooth, glabrous, internal appendage falcate, slightly exserted, glabrous; style apex shallowly depressed, cream. |
Seeds | broadly ovate, 8–9 × 6–7 mm, margin winged, faces smooth; coma 2–5 cm. |
ovate, 10–12 × 7–10 mm, margin very narrowly winged, faces smooth; coma 2–2.5 cm. |
Follicles | erect on upcurved pedicels, narrowly to broadly fusiform, 7.5–12.5 × 1.5–2.5 cm, apex acuminate, smooth, densely hirtellous to velutinous. |
erect on upcurved pedicels, ovoid, 5–6.5 × 2–2.5 cm, apex apiculate to acuminate, longitudinally ridged, tomentulose. |
2n | = 22. |
|
Asclepias obovata |
Asclepias vestita |
|
Phenology | Flowering May–Sep; fruiting Jul–Oct. | Flowering Apr–Jul; fruiting May–Sep. |
Habitat | Hills, slopes, flats, ridges, sandhills, ditches, seeps, bogs, sandstone, sandy, rocky, silty, and clay soils, pine flatwoods, pine savannas, pine, pine-oak, and bottomland hardwood forests, prairies, often following fires. | Flats, slopes, ridges, canyons, arroyos, foothills, alluvial fans, fields, granite, sandstone, sandy, clay, and rocky soils, desert scrub, chaparral, grasslands, oak, pine-oak, juniper, pinyon-juniper, and Joshua tree woodlands. |
Elevation | 0–200 m. (0–700 ft.) | 50–2000 m. (200–6600 ft.) |
Distribution |
AL; AR; FL; GA; LA; MS; OK; SC; TX
|
CA
|
Discussion | Asclepias obovata is a common milkweed of seasonally wet, sandy soils in pine woodlands of the Gulf Coastal Plain and (rarely) the southern Atlantic Coastal Plain. It is rare and considered to be of conservation concern in Arkansas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
W. L. Jepson (1923–1925) and R. E. Woodson Jr. (1954) segregated southern populations (Inyo, Kern, Los Angeles, San Bernardino, and Ventura counties) from northern populations (Fresno, Madera, Mariposa, Merced, Monterey, San Benito, San Joaquin, and San Luis Obispo counties) as varieties or subspecies. Of their distinguishing characters, only flower color is consistently different between these segments of the range: northern populations have pale green corollas with at most a pink tinge, whereas southern populations have pale burgundy to red-violet corollas. There is a tendency for plants in southern populations to be smaller and become more evidently glabrate late in the season, but more robust and hairier plants can also be found in the south. Further research may support recognition of distinct taxa for these populations, but they are not recognized here. Asclepias vestita is similar to co-occurring A. californica in the absence of flowers or fruits, but plants of A. vestita tend to be more prostrate and compact and the leaves tend to be broader towards the base and more quickly glabrate. (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 | ||
Synonyms | A. vestita subsp. parishii, A. vestita var. parishii | |
Name authority | Elliott: Sketch Bot. S. Carolina 1: 321. (1817) | Hooker & Arnott: Bot. Beechey Voy., 363. (1839) |
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