Euphorbia commutata |
Euphorbia graminea |
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tinted euphorbia, tinted woodland spurge |
grassleaf spurge |
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Habit | Herbs, usually biennial, occasionally annual, with taproot. | Herbs, usually annual, rarely perennial, with slender, rarely tuberous, taproot. |
Stems | erect or ascending, decumbent and often branched near base, 10–40 cm, glabrous. |
erect or ascending, branched, 30–80(–110) cm, strigillose or glabrescent, sharply angled. |
Leaves | petiole usually 5–10 mm, 0–1 mm distally; blade usually oblanceolate to obovate, rarely ovate, 5–30 × 3–10 mm, base broadly attenuate, margins entire, apex usually obtuse to rounded, occasionally slightly retuse, surfaces glabrous; venation pinnate, midvein prominent. |
usually alternate, sometimes some opposite; stipules usually 0.2–0.5 mm, rarely rudimentary; petiole 0.4–5.9 mm, strigillose; blade ovate, elliptic, linear-elliptic, or oblong, 10–83 × 3–39 mm, base attenuate, rounded, or cuneate, margins entire, apex acute or obtuse, surfaces strigillose; venation occasionally obscure on narrow leaves, midvein conspicuous. |
Involucre | campanulate, 1.7–2.5 × 1.5–2.5 mm, glabrous; glands 4, crescent-shaped; 0.6–1 × 0.8–1.5 mm; horns divergent, 0.5–1.1 mm. |
campanulate or obconic, 1–1.8 × 0.8–1.7 mm, glabrous or strigillose toward rim; glands (1–)2–4, yellow to greenish, elliptic or oblong, 0.1–0.3 × 0.2–0.4 mm; appendages white to tinged purple, ovate and often hoodlike or forming narrow rim around distal margin of gland, 0.3–1.6 × 0.4–0.9 mm, entire. |
Staminate flowers | 9–15. |
30–40. |
Pistillate flowers | ovary glabrous; styles 0.9–1.3 mm, 2-fid. |
ovary glabrous; styles 0.7–1 mm, 2-fid from 1/2 to nearly entire length. |
Capsules | ovoid-globose, 2.5–3.2 × 3 mm, slightly lobed; cocci rounded to ± flattened, smooth, glabrous; columella 1.5–2 mm. |
ovoid-oblate, 2.5–3 × 3–3.5 mm, glabrous; columella 1.6–1.9 mm. |
Seeds | white to gray, broadly oblong-elliptic to ovoid or nearly globose, 1.5–2 × 1.3–1.6 mm, strongly small-pitted; caruncle irregularly winglike, conic, 0.6–1 × 0.7–0.9 mm. |
gray, brown, or nearly black, ovoid, circular or weakly angled in cross section, 1.5–1.7 × 1.3–1.5 mm, coarsely tuberculate with longitudinal rows of shallow pits; caruncle absent or punctiform, 0.1–0.2 mm. |
Cyathial | arrangement: terminal pleiochasial branches (2–)3(–4), 1–3+ times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct to basally subconnate, not imbricate, widely ovate, rhombic, or reniform, base cordate, rarely slightly perfoliate, margins entire, apex obtuse to rounded, mucronulate; axillary cymose branches 0–5. |
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Cyathia | peduncle 0.5–1 mm. |
in usually terminal, rarely axillary, dichasia, distal dichasial bracts often white; peduncle 0.4–4.5 mm (to 15 mm at first node of inflorescence), glabrous. |
Euphorbia commutata |
Euphorbia graminea |
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Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting year-round. |
Habitat | Bottomland and upland forests, bluffs and ledges, stream banks, glades, rarely fen margins. | Disturbed, weedy, or urban areas. |
Elevation | 50–1000 m. (200–3300 ft.) | 0–500 m. (0–1600 ft.) |
Distribution |
AL; AR; FL; GA; IA; IL; IN; KY; LA; MD; MI; MO; MS; NC; OH; OK; PA; SC; TN; VA; WI; WV; ON
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AR; CA; FL; LA; TX; Mexico; Central America; South America [Introduced in North America; introduced also in West Indies, Asia, Pacific Islands]
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Discussion | Euphorbia graminea occurs natively from northern South America to northern Mexico. The species is a variable and taxonomically complex entity whose boundaries are not well defined and are in need of further study. Euphorbia graminea is often weedy and has recently become established in warmer areas of the southern United States, where it will likely become more common in the future. In recent years, a cultivar of E. graminea has found considerable horticultural success and is marketed under the trade name "Diamond Frost." (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 300. | FNA vol. 12, p. 246. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Alectoroctonum |
Sibling taxa | ||
Synonyms | Galarhoeus austrinus, G. commutatus, Tithymalus commutatus | |
Name authority | Engelmann: in A. Gray, Manual ed. 2, 389. (1856) | Jacquin: Select. Stirp. Amer. Hist., 151. (1763) |
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