Plants acaulescent or short-stemmed, commonly suckering, trunks less than 2 m;rosettes not cespitose, 10–20 × 20-37 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. 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. 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. Capsules short-pedicellate, oblong, 3.5-8 cm, apex beaked. Seeds 6-8 mm (Flora of North America Editorial Committee, 2016).
Related invasive species
- Agave americana
Related Farm Practice
- Flora
- Hosts
- Light
A. americana is a large, rhizomatous succulent that grows in a wide range of habitats and soil types. Additionally, it is tolerant to salt spray, high temperatures, and extreme drought. Because this species spread by seeds, but also vegetatively by bulbils and rhizomes, it has the potential to escape from cultivation and rapidly colonize disturbed sites, roadsides, bare sand and coastal areas (ISSG, 2016). Currently, A. americana is considered a serious environmental weed by the IUCN (ISSG, 2016) and it is listed as invasive in many countries in Europe as well as in China, Japan, South Africa, Namibia, Tanzania, Bermuda, Australia, New Zealand, and New Caledonia among others (BioNET-EAFRINET, 2016;ISSG, 2016;DAISIE, 2016;PIER, 2016;Weeds of Australia, 2016). It is also known to have become invasive in Ethiopia, Kenya, Malawi, Rwanda, and Uganda.
A. americana negatively impacts populations of native and endangered plant species such as Cheirolophus crassifolius and Cremnophyton lanfrancoi on Malta and species such as Crambe wildpretii, Crambe pritzelii, and Asparagus arborescen s on the Canary Islands (ISSG, 2016).