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asclépiade à fleurs vertes, green antelopehorn milkweed, green comet milkweed, green milkweed

Feay's milkweed, Florida milkweed

Habit Herbs. Herbs.
Stems

solitary, erect to ascending, unbranched (rarely), (10–)20–125 cm, puberulent with curved trichomes, not glaucous, rhizomes absent.

solitary, erect, unbranched (rarely near base), 20–75 cm, minutely puberulent in a line with curved trichomes to glabrate, not glaucous, rhizomes absent.

Leaves

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

petiole 0–5 mm, puberulent with curved trichomes;

blade linear to broadly oval or nearly orbiculate, 2–13 × 0.8–6 cm, chartaceous, base cuneate to rounded, margins entire or crisped, apex acute or obtuse to truncate or emarginate, mucronate, venation brochidodromous, surfaces sparsely pilosulous to glabrate, margins ciliate, laminar colleters absent.

opposite, sessile, with 1 or 2 stipular colleters on each side of leaf base;

blade filiform, 2.5–10 × 0.1–0.15 cm, membranous, base cuneate, margins entire, apex acute, venation obscure, surfaces glabrous, laminar colleters absent.

Inflorescences

extra-axillary at upper nodes, sometimes branched at peduncle apex, sessile or pedunculate, 22–60-flowered;

peduncle 0–4 cm, puberulent with curved trichomes to pilosulous, with 1 caducous bract at the base of each pedicel.

terminal, sometimes branched, and often extra-axillary at upper nodes, sessile or pedunculate, 2–7-flowered;

peduncle 0–5 cm, puberulent with curved trichomes on 1 side, with 1 caducous bract at the base of each pedicel.

Pedicels

7–13 mm, pilosulous.

7–17 mm, minutely puberulent with curved trichomes on 1 side.

Flowers

erect to pendent;

calyx lobes narrowly lanceolate, 2–3 mm, apex acute, pilosulous;

corolla green to yellowish green, sometimes tinged red, lobes reflexed, oblong, 5–7 mm, apex acute, inconspicuously pilosulous at apex abaxially, glabrous adaxially;

gynostegium sessile;

fused anthers green, cylindric, 3–4 mm, wings triangular, widest at middle, closed, apical appendages ovate, marginally inflexed, apically deflexed;

corona segments green to cream, sometimes tinged red, sessile, laminar, margins incurved, appressed to column, 3–4 mm, greatly exceeded by style apex, apex obtuse, glabrous, internal appendage absent or obscure, glabrous;

style apex shallowly depressed, green.

erect;

calyx lobes narrowly lanceolate, 1.5–2.5 mm, apex acute, glabrous;

corolla white, sometimes pale lavender-tinged, inconspicuously striate, lobes spreading, lanceolate, 7–10 mm, apex acute to obtuse, glabrous;

gynostegium sessile;

fused anthers lavender, cylindric, 1.5–3 mm, wings narrowly right-triangular, open at base, apical appendages ovate;

corona segments white, sessile with a basal collar, cupulate, 2.5–4 mm, equaling to slightly exceeding style apex, apex obtuse, glabrous, internal appendage a laterally flattened, included crest, glabrous;

style apex shallowly depressed, lavender.

Seeds

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

coma 2.5–3 cm.

oval, 6–8 × 3–5 mm, margin winged, faces smooth;

coma 3.5 cm.

Follicles

erect on upcurved pedicels, fusiform to lance-ovoid, 6–10 × 1.5–2 cm, apex acuminate to attenuate, smooth, pilosulous.

erect on straight pedicels, fusiform, 9–12 × 0.3–0.6 cm, apex attenuate, smooth, glabrous.

2n

= 22.

Asclepias viridiflora

Asclepias feayi

Phenology Flowering Apr–Sep(–Oct); fruiting Jun–Nov. Flowering (Feb–)Apr–Sep(–Nov); fruiting Jun–Aug.
Habitat Slopes, ridges, bluffs, flats, canyons, arroyos, glades, fields, meadows, pastures, sandhills, dunes, pond edges, streamsides, playas, sandstone, limestone, gypsum, ser­pentine, dolomite, alluvium, silty, sandy, clay, rocky, and calcareous soils, prairies, desert grasslands, oak scrub, oak, oak-juniper, oak-hickory, pine-oak, and pine woodlands, forest openings and edges. Flats, streamsides, sandy soils, pine scrub and flatwoods, pine-palmetto scrub, prairies, hammocks.
Elevation 0–2300 m. (0–7500 ft.) 0–50 m. (0–200 ft.)
Distribution
from FNA
AL; AR; AZ; CO; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MD; MI; MN; MO; MS; MT; NC; ND; NE; NJ; NM; NY; OH; OK; PA; SC; SD; TN; TX; VA; WI; WV; WY; AB; MB; ON; SK; Mexico (Coahuila)
[WildflowerSearch map]
[BONAP county map]
from FNA
FL
[BONAP county map]
Discussion

Asclepias viridiflora is one of the milkweeds with spherical, greenish umbels and inconspicuous coronas (see also A. engelmanniana, A. hirtella, A. lanuginosa, A. longifolia, A. rusbyi, A. stenophylla). Prior to close examination, the tight green balls of open flowers appear to be merely in bud. The diversity in leaf morphology among individuals (linear to orbiculate) is remarkable, but has no taxonomic significance—the full range of variation may be found within single populations. This is the most widespread milkweed within the flora area, ranging across most of the United States (absent only from the westernmost states and most of New England) and southern Canada. It is nowhere abundant, but may be regularly encountered in suitable, thin-soiled prairie habitats, especially in the Great Plains. It is rare and considered to be of conservation concern on the margins of its range, in Alberta (Cypress, Forty Mile, and Warner counties), Arizona (Coconino, Gila, and Yavapai counties), Connecticut (New Haven County), Florida (Gadsden and Jackson counties), and New York (Columbia, Nassau, Richmond, and Suffolk counties).

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

Asclepias feayi is one of a trio of very slender milkweeds in the southeastern United States, along with A. cinerea and A. viridula. These species are divergent in floral morphology, but without flowers they are very difficult to distinguish (even in fruit), and they appear to be close relatives. However, A. feayi occurs primarily in peninsular central and southwestern Florida, from Lake to Collier counties, most commonly in scrub. A single disjunct population has been documented from Clay County in the northeastern part of the state (Hall 1896 [FLAS]). Asclepias cinerea and A. viridula are found in northern Florida or further north, in flatwoods. All three species are cryptic in the absence of flowers and appear to respond positively to fire and rainfall events. They are likely to be more common than is apparent because they are inconspicuous and emerge episodically. Nonetheless, numerous historical locations for A. feayi have been developed and are no longer capable of supporting populations, and its conservation status merits evaluation. An unusual putative hybrid with A. pedicellata represented by a single collection is documented from Marion County (Judd 2639 [FLAS]), suggested by the exactly intermediate floral morphology.

(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. 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. 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. 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
Synonyms Acerates ivesii, A. viridiflora var. lanceolata, A. viridiflora var. linearis Asclepiodella feayi
Name authority Rafinesque: Med. Repos., hexade 2, 5: 360. (1808) A. Gray: Proc. Amer. Acad. Arts 12: 72. (1876)
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