Very robust, stoloniferous herb; stem scarcely developed. Leaves 1-2 m x 15-25 cm, constricted above the broad, sheathing base, glaucous, remotely spinose-dentate, with a stout, blackish terminal spine 2-3 cm long. Scape (including inflorescence) 4-7(-10) m. Peduncle 8-15 cm in diameter, woody at maturity, equal to or shorter than the panicle, bearing triangular, leaf-like bracts. Panicle pyramidal; flowers aggregated in dense clusters at the ends of horizontal branches; leafy buds sometimes present in axils of bracteoles, replacing some or all of the flowers. Flowers (including ovary) 70-90 mm; perianth-segments linear-oblong, obtuse, erect, greenish- yellow. Filaments 70-80 mm, inserted on the hypanthial tube; anthers 30-35 mm. Capsule oblong, trigonous.