Solanum elaeagnifolium |
Solanum nigrum |
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|---|---|---|
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horse nettle, silver-leaf nightshade, white horse-nettle |
black nightshade, European black nightshade |
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| Habit | Herbs or shrubs, perennial, erect, rhizomatous, sparsely to densely armed, to 1 m, prickles orange to brown, straight, to 5 mm, densely silvery-pubescent, hairs sessile or subsessile, stellate, scalelike, 10–15-rayed, central ray shorter than lateral rays, lateral rays fused at center. | Herbs, annual or perennial, erect or sprawling, unarmed, to 1 m, glabrescent to moderately pubescent, hairs unbranched, to 1 mm, usually eglandular or occasionally glandular. |
| Leaves | petiolate; petiole 1–5 cm; blade simple, lanceolate to oblong, 5–15 × 0.5–3 cm, margins undulate, subentire to sinuate or shallowly lobed, lobe margins entire, base truncate to cuneate. |
petiolate; petiole 0.5–3 cm; blade simple, ovate, 3.5–7 × 2.2–5 cm, margins entire to coarsely toothed with 3–5 lobes per side, base truncate to cuneate. |
| Inflorescences | extra-axillary, unbranched, 3–5(–7)-flowered, 3–5 cm. |
extra-axillary, unbranched or occasionally forked, racemelike, (3–)4–10-flowered, 1–2 cm. |
| Pedicels | 1–3 cm in flower, reflexed and 1–3 cm in fruit. |
0.5–1 cm, spreading to occasionally recurved in flower and fruit. |
| Flowers | radially symmetric; calyx not accrescent, unarmed or with sparse prickles, 5–10 mm, densely silvery-stellate-pubescent, lobes linear-lanceolate; corolla pale to deep blue or violet, rarely white, pentagonal-stellate, 2–3(–3.5) cm diam., with abundant interpetalar tissue; stamens equal; anthers narrow and tapered, 6–9 mm, dehiscent by terminal pores; ovary glabrous to densely stellate-pubescent. |
radially symmetric; calyx not accrescent, unarmed, 1.5–2 mm, sparsely pubescent, lobes deltate, spreading to reflexed in fruit; corolla white with yellowish central star, stellate, 1–1.5 cm diam., without interpetalar tissue; stamens equal; anthers ellipsoidal, (1.8–)2–2.5 mm, dehiscent by terminal pores that open into longitudinal slits; ovary glabrous. |
| Berries | yellow to orange, drying brown or black, globose, 0.5–1.5 cm diam., glabrous, without sclerotic granules. |
dull or slightly shiny purple-black or green to yellowish green, globose, 0.5–1 cm diam., glabrous, without sclerotic granules. |
| Seeds | yellowish, flattened, 3–5 × 2–4 mm, minutely pitted. |
yellow, flattened, 1.8–2 × 1.5–1.6 mm, minutely pitted. |
| 2n | = 24, 48, 72. |
= 72. |
Solanum elaeagnifolium |
Solanum nigrum |
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| Phenology | Flowering Mar–Nov. | Flowering May–Oct. |
| Habitat | Dry sites, open woods, disturbed areas, roadsides, railroads, fields. | Disturbed areas, irrigated fields. |
| Elevation | 0–2100 m. [0–6900 ft.] | 0–2200 m. [0–7200 ft.] |
| Distribution |
AL; AR; AZ; CA; CO; FL; GA; ID; IL; IN; KS; KY; LA; MD; MO; MS; NC; NE; NM; NV; OK; OR; SC; TN; TX; UT; WA; Mexico; West Indies; South America (Argentina, Chile, Paraguay, Uruguay) [Introduced elsewhere in South America (Colombia, Peru), Eurasia (Mediterranean, Middle East, India, Pakistan), Africa, Australia]
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AK; CA; DC; FL; GA; IA; ID; MA; MD; ME; MO; MT; NC; NJ; NV; NY; OK; OR; PA; TX; UT; VA; WA; BC; NS; ON; Eurasia; n Africa [Introduced in North America; introduced also in Pacific Islands (New Zealand), Australia]
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| Discussion | Solanum elaeagnifolium has a disjunct native distribution. It occurs in arid regions of the southwestern United States and Mexico and also in Argentina, Chile, Paraguay, and Uruguay. North American plants are diploid, whereas those in Argentina are diploid, tetraploid, or hexaploid. It is invasive and considered a noxious weed in 21 states in the flora area as well as in many tropical and subtropical regions worldwide. It is toxic to livestock and can form large, rhizomatous patches that are difficult to eradicate. A white-flowered form has been recognized as Solanum elaeagnifolium forma albiflorum Cockerell. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Many regional floras have used Solanum nigrum as the name for various species in the black nightshade group, and it can be difficult to distinguish this species from S. emulans and S. nigrescens. Solanum nigrum can be distinguished from the native North American species of the black nightshade group (S. americanum, S. douglasii, S. emulans, S. interius, S. nigrescens) by its thicker peduncles and pedicels, larger seeds, and fruits lacking sclerotic granules. Solanum nigrum was probably introduced from northern Europe and has been locally naturalized in North America. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
| Parent taxa | ||
| Sibling taxa | ||
| Synonyms | S. nigrum subsp. schultesii | |
| Name authority | Cavanilles: Icon. 3: 22, plate 243. (1795) | Linnaeus: Sp. Pl. 1: 186. (1753) |
| Source | FNA vol. 14. | FNA vol. 14. |
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