Agave americana |
Agave sisalana |
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American agave, American century plant, centuryplant, maguey americano |
sisal, sisal hemp |
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Habit | Plants acaulescent or short-stemmed, commonly suckering, trunks less than 2 m; rosettes not cespitose, 10–20 × 20–37 dm. | Plants short-stemmed, commonly suckering with elongate rhizomes, trunks 0.4–1 m; rosettes not cespitose, 15–20 × 15–25 dm. | ||||
Leaves | erect, spreading to ascending, occasionally reflexed, 80–200 × 15–25 cm; blade light green to green or glaucous-gray, sometimes variegated or cross-zoned, narrowly to broadly lanceolate, smooth, rigid; margins nearly straight or undulate to crenate, armed, teeth single, 5–10 mm, 1–4 cm apart; apical spine dark brown to grayish, conical or subulate, 2–6 cm. |
spreading, 90–130 × 9–12 cm; blade green, slightly cross-zoned when immature, lanceolate, firm, adaxially plane, abaxially slightly convex; margins straight, finely fibrous, typically unarmed, teeth single prickles when present, 1–2 mm, 2–5+ cm apart; apical spine dark brown, subulate, 2–2.5 cm. |
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Scape | 5–9 m. Inflorescences paniculate, not bulbiferous; bracts persistent, triangular, 5–15 cm; lateral branches 15–35, horizontal to slightly ascending, comprising distal 1/3–1/2 of inflorescence, longer than 10 cm. |
5–6 m. Inflorescences paniculate, open, often bulbiferous; bracts persistent, triangular, 0.5–2 cm; lateral branches 10–15(–25), ascending, comprising distal 1/2 of inflorescence, longer than 10 cm. |
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Flowers | erect, 7–10.5 cm; perianth yellow, tube funnelform to cylindric, 8–20 × 12–20 mm, limb lobes erect, subequal, 20–35 mm; stamens long-exserted; filaments inserted above mid perianth tube, erect, yellow, 6–9 cm; anthers yellow, 25–35 mm; ovary 3–4.5 cm, neck constricted, 3–6(–8) mm. |
erect, 5.5–6.5 cm; perianth greenish yellow, tube urceolate, 15–18 × 10–12 mm, limb lobes erect, equal, 17–18 mm; stamens long-exserted; filaments inserted ca. mid perianth tube, erect, yellow, 5–6 cm; anthers yellow, 20–25 mm; ovary 2–2.5 cm, neck slightly constricted, 2–4 mm. |
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Capsules | short-pedicellate, oblong, 3.5–8 cm, apex beaked. |
not seen. |
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Seeds | 6–8 mm. |
unknown. |
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2n | = 138, 147, 149, 150. |
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Agave americana |
Agave sisalana |
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Phenology | Flowering winter–early spring. | |||||
Habitat | Sandy places along roadsides and in hammocks | |||||
Elevation | 0 m (0 ft) | |||||
Distribution |
sw United States; Mexico
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FL; s Mexico [Introduced in North America] |
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Discussion | Subspecies 2 (2 in the flora). Various chromosome numbers have been reported for Agave americana under a variety of names, typically without regard to the plant’s origin or its precise taxonomic disposition. Nonetheless, the species is most certainly a polyploid complex based on x = 30, with reports of n = 30 and 2n = 60, 120, and 180 documented by S. D. McKelvey and K. Sax (1933), H. Matsuura and T. Sutô (1935), E. B. Granick (1944), A. K. Sharma and U. C. Bhattacharyya (1962), M. S. Cave (1964), S. Banerjee and A. K. Sharma (1987), Huang S. F. et al. (1989) and B. Vijayavalli and P. M. Mathew (1990). Various dysploids have also been reported (A. F. Dyer et al. 1970; J. L. Strother and G. L. Nesom 1997). See H. S. Gentry (1982) for details. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Agave sisalana is frequently cultivated for its fiber and ornamental value. The plant is not known from the wild. As with A. desmettiana, capsules and seeds of this species are unknown. Capsules are known from A. kewensis (native to Chiapas), A. neglecta, and A. weberi, although no mature seeds have been observed. It may be that all are anciently selected cultivars that now persist only by vegetative means. None save A. kewensis is thought to occur in the wild. Plants similar to those found in Florida are known from Chiapas. Agave sisalana is an important source of fiber and probably was widely distributed by pre-Columbian people. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 26, p. 452. | FNA vol. 26, p. 454. | ||||
Parent taxa | Agavaceae > Agave | Agavaceae > Agave | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Name authority | Linnaeus: Sp. Pl. 1: 323. (1753) | Perrine: Trop. Pl., 87. (1838) | ||||
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