Euphorbia hirta |
Euphorbia nutans |
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pillpod sandmat, pillpod spurge |
eyebane, eyebane sandmat, eyebane spurge, nodding or upright spotted spurge, nodding 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. |
usually ascending, occasionally erect, often arched at tips, 20–80 cm, sparsely to moderately pilose to villous or with short, incurved hairs, hairs often concentrated at nodes and distally, occasionally in 2 bands along opposite sides of stem. |
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. |
opposite; stipules usually distinct, sometimes connate basally on one side of stem, small scales, irregularly toothed, fringed, or divided, 1–1.5 mm, sparsely to moderately villous distally; petiole 0.3–1.6 mm, moderately pilose to villous; blade oblong to oblong-lanceolate, 8–40 × 3–12 mm, base asymmetric, one side usually angled or rounded, other side ± truncate to cordate-auriculate, margins serrulate, apex angled with blunt tip, abaxial surface pale green or faintly to strongly reddish tinged, adaxial surface usually reddish-mottled or with conspicuous reddish spot, both surfaces usually sparsely to moderately pilose, especially toward base, sometimes glabrous; 3–5-veined from base, pinnate distally, veins faint. |
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. |
narrowly obconic, 0.5–1 × 0.3–0.7 mm, glabrous; glands 4, usually green, sometimes reddish purple, oblong to nearly circular, 0.2–0.4 × 0.3–0.5 mm; appendages white or pinkish, ovate to broadly elliptic, 0.2–1 × 0.2–1.5 mm, distal margin entire. |
Staminate flowers | 2–8. |
5–28. |
Pistillate flowers | ovary strigillose, often canescent when young; styles 0.2–0.6 mm, 2-fid 1/2 length. |
ovary glabrous; styles 0.6–2.5 mm, 2-fid 1/2 length. |
Capsules | subglobose to slightly oblate, 1–1.3 × 1.1–1.6 mm, strigillose; columella 0.7–1 mm. |
ovoid, 1.6–2.3 × 1.5–2.4 mm, glabrous; columella 1.4–1.6 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, sometimes with thin, white coating (often more persistent along angles than faces), elliptic-ovoid to ovoid, rounded-angular in cross section, 1–1.6 × 0.5–0.8 mm, surface finely and irregularly wrinkled, sometimes faintly so, or with indistinct, shallow, rounded cross ridges. |
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. |
solitary at distal nodes or in small, cymose clusters at branch tips; peduncle 0.5–2.5 mm. |
2n | = 12, 14, 22. |
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Euphorbia hirta |
Euphorbia nutans |
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Phenology | Flowering and fruiting year-round. | Flowering and fruiting spring–early fall. |
Habitat | Disturbed areas, roadsides, vacant lots, desert grasslands, mesquite woodlands, riparian forests with cottonwoods and willows, flood plain forests, pinelands, deciduous forests. | Stream banks, pond edges, disturbed portions of upland prairies, mesic to dry upland forest openings, pastures, fallow fields, railroads, roadsides, gardens, disturbed areas. |
Elevation | 0–1500 m. (0–4900 ft.) | 0–1600 m. (0–5200 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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AL; AR; CA; CT; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; MI; MN; MO; MS; NC; ND; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; VA; VT; WI; WV; WY; ON; QC; Mexico; Central America; South America; West Indies [Introduced in Eurasia]
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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.) |
Euphorbia nutans is probably native to at least central and eastern North America, but given its strongly weedy tendencies, it is difficult to know where it may be adventive in parts of the flora area. It is certainly introduced where it occurs in the Old World and probably in South America as well. D. G. Burch (1966) discussed the problems of assigning names to the four main entities in this nomenclatural complex (E. hypericifolia, E. hyssopifolia, E. lasiocarpa, and E. nutans) and determined that the oldest valid name for the relatively robust, temperate North American plants with ascending stems is E. nutans. See the treatment of 56. E. maculata for a discussion of the misapplication of that name to E. nutans. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 271. | FNA vol. 12, p. 278. |
Parent taxa | Euphorbiaceae > Euphorbia > sect. Anisophyllum | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Chamaesyce gemella, C. hirta, E. gemella | Chamaesyce lansingii, C. nutans, E. lansingii, E. preslii |
Name authority | Linnaeus: Sp. Pl. 1: 454. (1753) | Lagasca: Gen. Sp. Pl., 17. (1816) |
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