Euphorbia agraria |
Euphorbia jejuna |
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urban spurge |
dwarf broomspurge |
|
Habit | Herbs, perennial, with slender, spreading rootstock. | Herbs, perennial, with woody or fibrous-fleshy, napiform, branched or tuberous taproot, 3–15 mm thick. |
Stems | erect or ascending, unbranched or branched, 30–90 cm, glabrous. |
ascending to erect, densely emerging from woody crown, 5–15 cm, glabrous. |
Leaves | petiole absent; blade oblong-elliptic, 20–65 × 9–20 mm, base truncate to auriculate, margins entire, apex obtuse to rounded, surfaces glabrous; venation conspicuously pinnate, midvein prominent. |
opposite; stipules connate into lacerate or 2-fid, lanceolate or deltate scale, 0.5–0.9 mm, glabrous; petiole 0.3–0.9 mm, glabrous; blade orbiculate-obovate, ovate, or elliptic, 3–6(–8) × 1.8–5 mm, base moderately asymmetric, rounded to truncate, margins entire, apex blunt to acute, surfaces glabrous; 2–3-veined from base but usually only midvein conspicuous. |
Involucre | campanulate, 2.2–3 × 1.8–2 mm, glabrous; glands 4, crescent-shaped; 0.6–1 × 1–2 mm; horns slightly divergent to convergent, 0.1–0.2 mm. |
broadly campanulate, 1.2–1.5 × 0.8–1.2 mm, glabrous; glands 4, yellowish to green or purplish, oblong, 0.2–0.4 × 0.5–1 mm; appendages erect or spreading, white, 0.3–0.6 × 0.8–1.2 mm, usually deeply dissected into 4–5 acuminate lobes, rarely undivided, when divided distal margin rarely entire or crenate. |
Staminate flowers | 15–20. |
12–35. |
Pistillate flowers | ovary glabrous; styles 1.2–2 mm, 2-fid. |
ovary glabrous; styles 0.4–0.5 mm, unbranched thickened-clavate. |
Capsules | globose, 2–2.8 × 2.2–2.7 mm, 3-lobed; cocci rounded, smooth except finely granulate toward abaxial line, glabrous; columella 2.1–2.7 mm. |
ovoid and broadly triangular, 1.8–2.2(–2.7) × 1.5–2.1 mm, glabrous; columella 1.5–2.2 mm. |
Seeds | gray or whitish, ovoid-oblong, 2–2.1 × 1.2–1.3 mm, smooth; caruncle ± rounded and flattened, 0.8 × 0.6 mm. |
whitish, oblong, 4-angled in cross section, adaxial faces concave, with long raphe between, 1.5–2(–2.3) × 0.6–0.8 mm, dimpled with faint irregular transverse wrinkles or with up to 10 low, rounded transverse ridges. |
Cyathial | arrangement: terminal pleiochasial branches 8–15, 1–2 times 2-branched; pleiochasial bracts similar in shape but shorter and narrower than distal leaves; dichasial bracts distinct, rhombic to reniform, base obtuse, margins entire, apex obtuse, mucronate; axillary cymose branches 12–23. |
|
Cyathia | peduncle 0–2 mm. |
solitary at distal nodes; peduncle 0.8–1.5 mm. |
Euphorbia agraria |
Euphorbia jejuna |
|
Phenology | Flowering and fruiting spring–summer. | Flowering and fruiting early spring–summer. |
Habitat | Grasslands, roadside banks, pastures. | Thin calcareous soils (caliche) on limestone hills. |
Elevation | 200–1600 m. (700–5200 ft.) | 500–900 m. (1600–3000 ft.) |
Distribution |
KS; MT; NE; NY; PA; WA; WY; AB; SK; Europe [Introduced in North America]
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TX; Mexico (Chihuahua, Coahuila) |
Discussion | Euphorbia jejuna is known in the flora area from only a few collections in Mitchell, Nolan, Terrell, and Val Verde counties. The species is very similar to E. astyla, but differs in its more deeply divided involucral gland appendages and more definitely petiolate, rounder leaves. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 12, p. 298. | FNA vol. 12, p. 274. |
Parent taxa | Euphorbiaceae > Euphorbia > subg. Esula | Euphorbiaceae > Euphorbia > sect. Anisophyllum |
Sibling taxa | ||
Synonyms | Tithymalus agrarius | Chamaesyce jejuna |
Name authority | M. Bieberstein: Fl. Taur.-Caucas. 1: 375. (1808) | M. C. Johnston & Warnock: SouthW. Naturalist 5: 97, fig. [p. 98]. (1960) |
Web links |