Jättiagaave – Agave americana

Stem is absent or very short. The massive leaf rosette is up to 2 m tall and 3.7 m wide. Leaves are usually 30-40 or more, erect, narrowly to broadly lanceolate, 1-2 m × 15-20 cm, fleshy, spreading to ascending, occasionally reflexed. Blade is light green to green or glaucous-gray, sometimes variegated or cross-zoned, smooth, rigid. Leaf margins are smooth to undulate to crenate, or armed with 5-10 mm long teeth, and sometimes bear thread-like appendages. Leaf is tipped with a dark brown spine 1.5-6 cm. Inflorescence is a panicle 6-10 m tall, with 15-35 horizontal to slightly ascending lateral branches, not bulbiferous or bearing only few bulblets after anthesis, with persistent, triangular bracts 5-15 cm. Flowers are erect, 7-10.5 cm, with greenish yellow tubular perianth; tube funnel form to cylindric, 12-20 mm long; limb lobes erect, subequal, 20-35 mm. Stamens are yellow, ca. 2 × as long as perianth. Capsule is short-pedicellate, oblong, 3.5-8 cm, with beaked apex. Seeds are 6-8 mm.

The plant is monocarpic, i.e. the shoot dies after fruiting, but suckers produced from the base of the stem can continue growth. One shoot may live for 10 to 25 years. Bats, birds and insects pollinate the flowers.