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Florida milkweed, long-leaf milkweed

pineland milkweed

Habit Herbs. Herbs.
Stems

1–few, spreading to decumbent, unbranched, 25–70 cm, puberulent with curved trichomes, not glaucous, rhizomes absent.

1 (rarely more), erect to spreading, unbranched, 40–70(–200) cm, densely hirtellous to velutinous, not glaucous, rhizomes absent.

Leaves

opposite or alternate, sessile or petiolate, with 1 or 2 stipular colleters on each side of petiole, also in axil;

petiole 0–2 mm, puberulent with curved trichomes;

blade linear to linear-lanceolate, 5–18 × 0.2–1 cm, chartaceous, base cuneate, margins entire, apex acute to attenuate, sometimes mucronate, venation brochidodromous, surfaces scabridulous to puberulent with curved trichomes, especially on veins, margins ciliate, laminar colleters absent.

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.

Inflorescences

terminal and extra-axillary at upper nodes, sessile or pedunculate, 13–28(–36)-flowered;

peduncle 0–6 cm, puberulent with curved trichomes, with 1 caducous bract at the base of each pedicel.

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.

Pedicels

9–16 mm, puberulent with curved trichomes.

10–12 mm, densely hirtellous to velutinous.

Flowers

erect to spreading;

calyx lobes narrowly lanceolate, 1.5–2 mm, apex acute, puberulent with curved trichomes;

corolla white to greenish cream, purple at lobe tips, lobes reflexed, oblong, 3–5 mm, apex obtuse, glabrous;

gynostegial column 0.2–0.5 mm;

fused anthers green or brown, cylindric, 1–1.5 mm, wings triangular to trapezoidal, widest at middle, slightly open at tip, apical appendages ovate;

corona segments pinkish lavender to red-violet, often with white apex, often a darker red-violet stripe or at base, sessile, laminar, strongly dorsally compressed, margins incurved, appressed to column, curved to subsaccate, 2–2.5 mm, exceeding point of anther wings, greatly exceeded by style apex, apex obtuse to truncate, glabrous, internal appendage absent or obscure, glabrous;

style apex shallowly depressed, greenish cream to green.

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.

Seeds

ovate, 11–12 × 7–8 mm, margin winged, faces smooth;

coma 4–5 cm.

broadly ovate, 8–9 × 6–7 mm, margin winged, faces smooth;

coma 2–5 cm.

Follicles

erect on upcurved pedicels, narrowly fusiform, 8–13.5 × 0.7–1.2 cm, apex attenuate, smooth, puberulent with curved trichomes.

erect on upcurved pedicels, narrowly to broadly fusiform, 7.5–12.5 × 1.5–2.5 cm, apex acuminate, smooth, densely hirtellous to velutinous.

Asclepias longifolia

Asclepias obovata

Phenology Flowering (Jan–)Feb–Sep(–Oct); fruiting Apr–Aug. Flowering May–Sep; fruiting Jul–Oct.
Habitat Bogs, swamps, flats, ditches, depressions, pond edges, sandy, clay, and rocky soils, wet prairies, pine flatwoods, oak woodlands, savannas, pastures, often following fires. 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.
Elevation 0–100 m. (0–300 ft.) 0–200 m. (0–700 ft.)
Distribution
from FNA
AL; DE; FL; GA; LA; MS; NC; SC; VA
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; FL; GA; LA; MS; OK; SC; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Asclepias longifolia has sometimes been treated to include A. hirtella as conspecific, as discussed under that species. As circumscribed here, the distribution of A. longifolia extends along the Atlantic Coastal Plain south of Delaware to Florida and westward to the Mississppi River. Reports of A. longifolia from west of the Mississippi River in Louisiana and in Texas are assigned here to A. hirtella. Hence, the range of A. longifolia in Louisiana is extremely limited, and the conservation status of this species warrants assessment in that state (Livingston, Saint Helena, Saint Tammany, Tangipahoa, and Washington parishes). Reports of A. longifolia from Maryland and West Virginia have not been confirmed, and the species is considered extirpated from Delaware. Otherwise, it is rare at the northern extent of its range and considered to be of conservation concern in North Carolina and Virginia (Greensville and Prince George counties).

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

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.)

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. 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. 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. 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
Synonyms Acerates floridana, A. longifolia, A. floridana
Name authority Michaux: Fl. Bor.-Amer. 1: 116. (1803) Elliott: Sketch Bot. S. Carolina 1: 321. (1817)
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