Asclepias involucrata
Asclepias cinerea
dwarf milkweed, largeseed milkweed
ashy milkweed, Carolina milkweed
1–15, decumbent, unbranched or branched near base, 5–18 cm, puberulent with curved trichomes to pilosulous, not glaucous, rhizomatous.
1, erect, unbranched (rarely branched), 20–100 cm, minutely puberulent in a line with curved trichomes to glabrate, not glaucous, rhizomes absent.
opposite or subopposite to alternate, petiolate, with 1 or 2 stipular colleters on either side of petiole;
petiole 1–2 mm, pilosulous to glabrate;
blade linear to narrowly lanceolate, 1.5–12 × 0.2–0.8 cm, chartaceous, base cuneate to truncate, margins sometimes crisped, apex acute, mucronate, venation obscure to faintly eucamptodromous, surfaces sparsely pilosulous to glabrate, midvein puberulent with curved trichomes to pilosulous, margins densely ciliate, laminar colleters absent.
opposite, sessile, with 1 or 2 stipular colleters on each side of leaf base;
blade filiform, 2–9 × 0.1–0.15 cm, membranous, base cuneate, margins entire, apex acute, mucronate, venation obscure, surfaces glabrous, laminar colleters absent.
terminal, sessile, 6–35-flowered, bracts few.
terminal, branched, and extra-axillary at upper nodes, pedunculate, 2–8-flowered;
peduncle 0.5–1.7 cm, puberulent with curved trichomes on 1 side, with 1 caducous bract at the base of each pedicel.
12–19 mm, puberulent with curved trichomes to pilosulous.
10–25 mm, minutely puberulent with curved trichomes on 1 side.
erect to spreading;
calyx lobes elliptic, 2.5–3 mm, apex acute, pilosulous;
corolla green, sometimes tinged pink or red (especially abaxially), lobes reflexed, elliptic, 4.5–6 mm, apex acute, glabrous;
gynostegial column 0.5–1 mm;
fused anthers brown, cylindric, 1.5–2 mm, wings right-triangular, slightly open at tip, apical appendages ovate;
corona segments cream, usually with a pink or red dorsal stripe, subsessile, conduplicate, 3.5–4.5 mm, slightly exceeding style apex, apex truncate with a spreading tip, glabrous, internal appendage falcate, exserted, sharply inflexed towards the style apex, glabrous;
style apex shallowly depressed, cream or greenish cream to pink.
spreading to pendent;
calyx lobes lanceolate, 1.5–2 mm, apex acute, glabrous;
corolla cream, tinged gray, pink, or purple, faintly striate, lobes reflexed with spreading tips, elliptic, 4–5 mm, apex acute to obtuse, glabrous;
gynostegial column 0–0.5 mm;
fused anthers green, cylindric, 1.5–2 mm, wings narrowly right-triangular, open, apical appendages deltate;
corona segments cream, tinged gray, pink, or purple, sessile, conduplicate, dorsally flattened, 2–3 mm, equaling style apex, apex truncate with a proximal tooth on each side, glabrous, internal appendage a laterally flattened, included crest, glabrous;
style apex shallowly depressed, white.
ovate, 7–8 × 5–6 mm, margin thickly winged, faces papillose and rugulose, lepidote;
coma 1.5–2 cm.
ovate, 6–7 × 4–5 mm, margin thickly winged, faces sparsely papillose;
coma 2.5–3 cm.
erect on upcurved pedicels, ovoid, 4.5–5.5 × 1.5–2 cm, apex acuminate, rugose, faintly striate, minutely puberulent with curved trichomes to pilosulous.
erect on straight pedicels, fusiform, 8–12 × 0.3–0.7 cm, apex long-attenuate, smooth, glabrous.
Asclepias involucrata
Asclepias cinerea
Despite the common name dwarf milkweed, Asclepias involucrata is larger than the sympatric A. uncialis, to which it bears a great similarity in the absence of flowers or fruit. In such conditions, A. involucrata is highly cryptic among the short-statured bunch grasses with which it grows. It senesces typically by summer’s end, contributing to the impression that the species is not common. It has occasionally been circumscribed to include A. macrosperma (for example, E. Sundell 1994), although the distinctions made by R. E. Woodson Jr. (1954) were sound. Nonetheless, where the ranges of these largely parapatric species meet, in an arc from northwestern New Mexico to central Arizona, plants of intermediate morphology can be found. It is unknown whether these represent relics of the speciation process or examples of recent hybridization. Asclepias involucrata is rare and of conservation concern in Colorado (Baca, Bent, and Las Animas counties) and Oklahoma (Cimarron County). It is probably extirpated from Kansas (Stevens County), where it is known from a single, historical record. Reports from northern Arizona, southwestern Colorado, and Utah are based on records of A. macrosperma.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Similarities between Asclepias cinerea and A. feayi are discussed under the latter species. Asclepias cinerea inhabits flatwoods mostly north of the range of A. feayi, co-occurring only in Clay County as far as is known. Asclepias cinerea is sympatric with another similar species, A. viridula, across northern Florida. That species tends to grow in wetter woods and meadows than A. cinerea. In flower, they are easily distinguished by the spreading to pendent flowers, ashy lavender corollas, and corona segments with included, crestlike appendages of A. cinerea (versus erect to spreading flowers, green to brownish corollas, and corona segments with exerted, falcate appendages of A. viridula). Asclepias cinerea barely enters southeastern Alabama (Covington, Geneva, and Houston counties), and the species is considered to be of conservation concern in that state. Emergence and flowering of this species appears to be stimulated by precipitation events and/or fire.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
KS Wildflowers
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
