Euphorbia hirta |
Euphorbia platyphyllos |
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pillpod sandmat, pillpod spurge |
broad-leaf spurge |
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Habit | Herbs, annual or perennial, with slender to thickened taproot. | Herbs, annual, with taproot. |
Stems | usually erect to ascending, rarely prostrate or decumbent, 10–50(–75) cm, usually both strigillose and hirsute. |
erect, unbranched or branched, 15–80 cm, usually glabrous, rarely pilose. |
Leaves | opposite; stipules usually distinct, rarely connate at base, undivided or divided into 2–4 narrowly deltate to linear-subulate segments, 0.5–1.8(–2.9) mm, pilose, often with light-colored, minute circular glands at base; petiole 1–3 mm, usually both strigillose and hirsute; blade ovate to rhombic, 7–43 × 3–18 mm, base strongly asymmetric, one side rounded or slightly cordate to truncate, the other cuneate to attenuate, margins serrulate to double serrulate, apex acute, surfaces often with red spot in center, usually strigose to hirtellous, rarely glabrescent; 3–5-veined from base. |
petiole absent; blade oblanceolate or obovate, 20–50 × 5–10 mm, base subcordate or cuneate, margins finely serrulate, apex usually acute, occasionally obtuse, occasionally mucronulate, surfaces usually sparsely pilose, occasionally glabrate; venation pinnate, midvein prominent. |
Involucre | obconic, 0.6–1.2 × 0.4–0.9 mm, strigillose; glands 4, greenish to pink, circular, oblong, or reniform, 0.1–0.2 × 0.1–0.2 mm; appendages white to pink, flabellate, subcircular, or transversely oblong, rarely absent, (0–)0.1–0.6 × (0–)0.1–0.7 mm, distal margin usually entire, rarely slightly lobed. |
cupulate, 0.9–1.2 × 1.3–1.6 mm, sparsely pilose; glands 4, elliptic to ovate, 0.5–0.7 × 0.7–1 mm; horns absent. |
Staminate flowers | 2–8. |
10–12. |
Pistillate flowers | ovary strigillose, often canescent when young; styles 0.2–0.6 mm, 2-fid 1/2 length. |
ovary glabrous, styles 1.6–1.8 mm, 2-fid. |
Capsules | subglobose to slightly oblate, 1–1.3 × 1.1–1.6 mm, strigillose; columella 0.7–1 mm. |
globose or subglobose, 2.5–3 × 2.5–3 mm, slightly 3-lobed; cocci rounded, sparsely verrucose, glabrous; columella 1.9–2.1 mm. |
Seeds | brownish red to orange or pink, narrowly ovoid, 4-angled in cross section, 0.7–0.9 × 0.5–0.7 mm, usually rugulose or with 3–6 low transverse ridges, rarely nearly smooth. |
dark brown, ovoid, dorsiventrally compressed, 2–2.2 × 1.5–1.7 mm, smooth; caruncle ± reniform, 0.2–0.5 × 0.2–0.5 mm. |
Cyathia | in dense, axillary and terminal, capitate glomerules, with reduced, bractlike leaves subtending cyathia, axillary glomerules either sessile or at tips of elongated, leafless stalks; peduncle 0.4–2.1 mm. |
peduncle absent. |
Cyathial | arrangement: terminal pleiochasial branches (3–)5, proximalmost node 3-branched, more distal ones 1–3 times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct, ovate-triangular, base obtuse, margins finely serrulate, apex obtuse, mucronulate; axillary cymose branches 0–7(–14). |
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Euphorbia hirta |
Euphorbia platyphyllos |
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Phenology | Flowering and fruiting year-round. | Flowering and fruiting summer–fall. |
Habitat | Disturbed areas, roadsides, vacant lots, desert grasslands, mesquite woodlands, riparian forests with cottonwoods and willows, flood plain forests, pinelands, deciduous forests. | Lake shores, roadsides, waste places. |
Elevation | 0–1500 m. (0–4900 ft.) | 0–500 m. (0–1600 ft.) |
Distribution |
AL; AR; AZ; CA; FL; GA; LA; MS; NC; NM; NY; SC; TX; Mexico; Central America; South America; West Indies; Bermuda [Introduced in North America; introduced also in Europe, Asia, Africa, Australia]
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MA; MI; NC; NY; OH; PA; RI; TN; VT; WA; ON; s Europe [Introduced in North America; introduced also in South America (Argentina, Chile, Paraguay)] |
Discussion | Euphorbia hirta is a widespread weed that is distributed throughout tropical and subtropical regions of the world. It is probably native to at least central Mexico, and its native range possibly extends from South America to the southern United States. In many places within the flora area the species is certainly introduced, and it has been recorded as a waif from several states (for example, Maryland, Michigan, and Virginia). Euphorbia pilulifera Linnaeus, a rejected name that is a heterotypic synonym of the Asian E. parviflora Linnaeus, has been misapplied to North American material of E. hirta in the past. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 271. | FNA vol. 12, p. 307. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > subg. Esula |
Sibling taxa | ||
Synonyms | Chamaesyce gemella, C. hirta, E. gemella | Galarhoeus platyphyllos, Tithymalus platyphyllos |
Name authority | Linnaeus: Sp. Pl. 1: 454. (1753) | Linnaeus: Sp. Pl. 1: 460. (1753) |
Web links |