Euphorbia myrsinites |
Euphorbia discoidalis |
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broad leaf glaucous spurge, donkey tail, myrtle or creeping or blue spurge, myrtle spurge |
summer spurge |
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Habit | Herbs, usually perennial, occasionally biennial, with taproot. | Herbs, perennial, with spreading rootstock. |
Stems | erect or semiprostrate, unbranched or branched, 15–40 cm, succulent, glabrous. |
erect or ascending, unbranched, solitary or few, previous year's dead stems not persistent, 45–70 cm, usually densely puberulent to sericeous, rarely glabrous. |
Leaves | petiole 0–2 mm; blade obovate, obovate-oblong, lanceolate, orbiculate, or suborbiculate, 2–30 × 3–17 mm, fleshy, base truncate or attenuate, margins entire or finely denticulate, apex acute to obtuse, cuspidate or strongly mucronate, surfaces glabrous; venation and midvein inconspicuous. |
alternate; stipules to 0.1 mm; petiole (0–)1–2 mm (or absent), densely puberulent; blade usually linear, rarely ovate, 25–55 × 1.5–4 mm, base cuneate, margins entire, revolute, apex rounded, abaxial surface glabrous or puberulent to sericeous, adaxial surface glabrous; venation often obscure on smaller leaves, midvein conspicuous. |
Involucre | campanulate, 2.4–2.6 × 2.3–2.5 mm, glabrous; glands 4, trapezoidal, 1–1.5 × 1.5–2.5 mm; horns divergent, thick, tips rounded, dilated, 0.5–0.9 mm. |
campanulate, 1.2–1.4 × 1.2–2 mm, sparsely to densely puberulent; glands 5, green, reniform, 0.2–0.3 × 0.5–0.6 mm; appendages white, orbiculate to oblong, (0.5–)1–1.7 × 1–1.5 mm, entire. |
Staminate flowers | 6–12. |
20–25. |
Pistillate flowers | ovary glabrous; styles 2.5–2.8 mm, usually unbranched. |
ovary glabrous or sparsely strigose; styles 0.5–1.1 mm, 2-fid at apex to 1/2 length. |
Capsules | subglobose, 5–7 × 5–6 mm, unlobed; cocci rounded to subangular, smooth, glabrous; columella 4.5–5 mm. |
globose, 1.8–3 × 2.5–4.8 mm, glabrous or sparsely strigose; columella 2.3–2.5 mm. |
Seeds | brownish to grayish, oblong, 2.8–4.5 × 2–3.2 mm, vermiculate-rugose; caruncle substipitate, trapezoidal or mushroom-shaped, 1.3–1.5 × 0.6–0.8 mm. |
light gray, ovoid, 2 × 1.2–1.3 mm, smooth or with few, very shallow depressions; caruncle absent. |
Cyathial | arrangement: terminal pleiochasial branches 2–12, each 1–2 times 2-branched; pleiochasial bracts similar in shape and size to distal leaves; dichasial bracts distinct, suborbiculate or reniform, base truncate, margins entire or minutely denticulate, apex obtuse, mucronulate; axillary cymose branches 0–4. |
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Cyathia | peduncle 0.5–1 mm. |
in terminal pleiochasia; peduncle 5–15 mm, filiform, glabrous or very sparsely puberulent to sericeous. |
Euphorbia myrsinites |
Euphorbia discoidalis |
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Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting late spring–fall. |
Habitat | Scrub oak communities, open ground near forests, shrub-steppes. | Sand hills, pine savannas, woodland borders, open fields with sandy soils. |
Elevation | 0–2400 m. (0–7900 ft.) | 0–150 m. (0–500 ft.) |
Distribution |
CA; CO; ID; MT; NM; OR; UT; WA; WY; BC; s Europe; w Asia [Introduced in North America]
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AL; FL; GA; LA; MS; TX
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Discussion | Euphorbia myrsinites is cultivated in much of the flora area, where it can tolerate cold winters. In some areas, it can locally escape from cultivation. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
M. J. Huft (1979) remarked that Euphorbia discoidalis is uncommon west of Alabama and referred many narrow-leaved specimens from Louisiana and Texas to E. corollata. K. R. Park (1998) included them in an expanded E. discoidalis, and that is followed here. The western populations can be distinguished from E. corollata by their shorter involucral gland appendages and revolute leaf margins. Further study of these western populations is warranted. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 305. | FNA vol. 12, p. 245. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Alectoroctonum |
Sibling taxa | ||
Synonyms | Tithymalus myrsinites | Tithymalopsis discoidalis |
Name authority | Linnaeus: Sp. Pl. 1: 461. (1753) | Chapman: Fl. South. U.S., 401. (1860) |
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