Plants acaulescent, sparsely suckering; rosettes usually solitary, (4-)5-8 × (5-)10-15 dm, rather open. Leaves ascending, 30-60 (-70) × 15-27 cm; blade glaucous-gray to gray-green, not cross-zoned, lanceolate to broadly lanceolate, rigid, adaxially concave, abaxially convex; margins straight, armed, teeth single, well defined, (5-)7-10 mm, 1.5-2 cm apart; apical spine dark brown to gray, subulate, 3-5(-10) cm. Scape 2-7 m. Inflorescences paniculate, not bulbiferous, dense; bracts persistent, lanceolate, (3-)5-10 cm; lateral branches 12-20, slightly ascending, comprising distal 1/2-2/3 of inflorescence, longer than 10 cm. Flowers 21-48 per cluster, erect, 6.8-9 cm; perianth yellow to yellow-green, tube funnelform, 14-22 × 15-22 mm, limb lobes erect, slightly unequal, 18-24 mm; stamens long-exserted; filaments inserted irregularly ca. mid perianth tube, erect, yellow, 5-6.5 cm; anthers yellow, 25-30 mm; ovary 3-4 cm, neck constricted, 2-8 mm. Capsules short-pedicellate, oblong to obovoid, 4-5.7 cm, apex beaked. Seeds 6-7 mm.
Flowering summer--early fall. Gravelly to rocky, often calcareous places in grasslands, desert scrub, pinyon-juniper, and oak woodlands; 1200--2000 m; Tex.; nw Mexico.
Agave havardiana hybridizes with A. lechuguilla to form A. × glomeruliflora, with which it may also hybridize.