Senna occidentalis |
|
---|---|
coffee senna, septicweed |
|
Habit | Herbs, perennial, bushy, to 2.2 m; branches dark green and blackish. |
Leaves | mesophyllous, 11–26 cm, glabrous or glabrate; stipules caducous; extrafloral nectary 1, base of petiole, sessile or subsessile; leaflet pairs 4 or 5(or 6), blades lanceolate- or ovate-acuminate, 45–100 × 12–38 mm. |
Racemes | usually (1 or)2–5-flowered; bracts caducous, longer than bud, often blackish green. |
Pedicels | 8–21 mm. |
Flowers | monosymmetric; calyx pinkish or fuscous; corolla yellow, longest petal 12–17 mm; androecium heterantherous, stamens 6, staminodes 3 + 1; anthers of middle stamens 3.2–5.2 mm, of abaxial stamens 4.9–6.6 mm, elongated beyond pores, dehiscing by U-shaped pore, apical appendage linguiform, thickened; gynoecium incurved, ovules 40–60; ovary densely hairy; style slightly incurved. |
Legumes | ascending, flat, slightly curved or straight, linear, 80–135 × 6.5–9.5 mm, corrugated over seeds, dehiscent. |
Seeds | olive green or brownish, obovoid. |
2n | = 26, 28. |
Senna occidentalis |
|
Phenology | Flowering mid summer–early winter. |
Habitat | Disturbed habitats, waste places, roadsides. |
Elevation | 0–1200 m. (0–3900 ft.) |
Distribution |
AL; AR; FL; GA; IA; IL; IN; KS; LA; MA; MD; MO; MS; NC; NY; OK; SC; TN; TX; VA; Mexico; Central America; South America; West Indies [Introduced in North America; introduced also in tropical and subtropical Eurasia, Africa, Australia]
|
Discussion | Although Senna occidentalis is probably native to the tropical New World, the species is now weedy in so many countries worldwide, including also other parts of the New World, that the exact range of its geographic distribution as a native is a matter of speculation (H. S. Irwin and R. C. Barneby 1982). In the flora area, it is considered as naturalized (R. Kral et al. 2012; R. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. |
Parent taxa | Fabaceae > subfam. Caesalpinioideae (excluding Mimosoid clade) > Senna |
Sibling taxa | |
Synonyms | Cassia occidentalis, Ditremexa occidentalis |
Name authority | (Linnaeus) Link: Handbuch 2: 140. (1829) |
Web links |