South American tobacco

Herbs, perennial, [or soft-wooded small trees], from basal rosette that soon merges with cauline leaves. Stems single or multiple, stout, branches erect, 4–30 dm, viscid-pubescent. Rosette leaves sessile; blade elliptic, to 50 cm, base decurrent and often auriculate or clasping, surfaces viscid-pubescent. Cauline leaves sessile; proximal blades elliptic, distal elliptic to elliptic-ovate, decreasing in size distally, 20–50 cm, base auriculate, apex acute to acuminate, sur­faces viscid-pubescent. Inflorescences branched panicles with congested branches, appearing moplike, leafy; flowering crepuscular. Pedicels 0.5–1.5 cm (nodding, flowers pendent). Flowers: calyx green, oblong or subglobose (somewhat twisted), 1–1.8 cm, viscid-pubescent, lobes erect, deltate to triangular, equal or nearly so, much shorter than tube; corolla white, straight or very slightly curved, 6–9 cm (excluding limb), minutely viscid-pubescent without, tube white, cylindric, straight or slightly curved, 2 cm × 1–2 mm, throat 40–70 mm, glabrous or minutely puberulent internally, ventricose and inflated in middle to distal 1/3 (often somewhat asymmetrically), narrowing toward apex with constriction at mouth, 5 mm diam., limb spreading, tips somewhat reflexed, white, stellate, 1.5–2 cm diam., lobes white, broadly triangular, acute apically; stamens inserted subequally at base of throat, included; filaments unequal, 4 longer, 4–7 cm, just reaching corolla mouth, 1 slightly shorter, 4–6 cm, pubescent at insertion point; style straight, just exceeding the 4 longer stamens, slightly exserted. Capsules ovoid, 1.5–1.8 cm. Fruiting calyces not tearing at sinuses, almost completely covering capsule. Seeds 0.5 mm. 2n = 24.

Flowering year-round. Disturbed areas, abandoned gardens; 0–2000 m; introduced; Ariz., Calif.; South America (Argentina, Bolivia); introduced also in Europe (Germany, Sweden, United Kingdom).

Nicotiana sylvestris is widely cultivated and has been recorded as escaping, self-sowing, and persisting in disturbed areas. Most herbarium specimens have been collected from gardens or greenhouses, but the ease with which the species self-sows means it is likely to become at least ephemerally naturalized in areas with little frost.