YUCCA
Yucca
L., Sp. Pl. 1. 319. 1753; Gen. Pl. 5: 150. 1754; Bailey, Stand. Cyclop. Hort. 6: 3529. 1917; Hess & Robbins, Fl. North Amer. @ eFloras.org 26: 423; Akhter & Ghazanfar, Fl. Pak. @ eFloras.org p. 2.
Perennial, shrubby plants, usually with a trunk or small trees. Leaves sessile, in rosettes on caudices or at branch ends; blade linear-lanceolate, expanded basally, usually rigid, occasionally fleshy, margins entire or denticulate, often filiferous and separating into elongating fibres, corneous (hardy), apex mostly sharp pointed. Inflorescence erect or rarely pendent, paniculate or racemose, sometimes paniculate proximally and racemose distally. Flowers nodding, pedicellate, bracteate, bisexual, actinomorphic, hypogynous. Perianth campanulate or globose; tepals 6, similar, fleshy, usually free or connate at base, whitish to cream or tinged slightly with green or purple. Stamens 6, filaments fleshy, included, smooth, papillose or granular; anthers small, hardly distinguished from filaments. Ovary superior, obovoid or oblong-cylindrical, usually green, 3-locular or 6-locular with false septa, 3-lobed; style white to dark green, often thick; stigma usually 3-lobed. Fruit erect or pendent, capsular or baccate. Seeds many per locule, usually black, occasionally grey, flattened, round, rarely obovate or ovate.
52 species
Yucca aloifolia
Yucca aloifolia
L., Sp. Pl. 1: 319. 1753; Bailey, Stand. Cyclop. Hort. 6: 3531. 1917; Hess & Robbins, Fl. North Amer. @ eFloras.org 26: 429; Akhter & Ghazanfar, Fl. Pak. @ eFloras.org p. 2; Dracaena lenneana Regel, Gartenflora 20: 149. 1871; Sarcoyucca aloifolia (L.) Linding., Beih. Bot. Centralbl. 50(1): 446. 1933; Yucca serrulate Haw., Syn. Pl. Succ. 70. 1812.
Evergreen, erect, multi-trunked shrub or small tree, 1-4 m tall with stems reaching 10 cm in diameter. Plants rarely branched, offsets often produced from roots forming thickets; lower portions of the trunk may be skirted and concealed by persistent brown-coloured dead leaves. Leaves evergreen, forming terminal rosettes, sessile with overlapping bases; leaf lamina erect in younger leaves, spreading and reflexed in mature leaves, linear to lanceolate in outline, 12-40 cm x 2.5-6 cm, dark green, flat or slightly concave, thick, rigid and leathery, margin usually sharply denticulate or rarely entire, apex strongly pungent, gradually ending in sharp rigid spine. Inflorescence a large terminal panicle, 20-60 cm long, 1/4 to 1/2 within leaf rosette, branches usually ascending, axis angular. Flowers large, 3-4 cm x 5-7 cm, cream-coloured tinged with purple, pendulous, nodding, fragrant, bracteate, bisexual, actinomorphic, hypogynous. Pedicels shorter or as long as flowers, articulate at apex, persistent. Perianth bell-shaped, 5-7 cm in diameter; tepals 6, in 2 whorls, similar, free, creamish-white, often tinged purple on outer surface, 3-4 cm x 2-2.3 cm, ovate or ovate- oblong. Stamens 6, free, in 2 whorls, similar; filaments ca. 2 cm long, included, white, fleshy, dilated distally, minutely papillose; anthers small, hardly distinguished from filaments, 2-3 mm long. Ovary light green, shortly stipitate, superior, ca. 2.5 cm long, oblong-cylindrical, 3-lobed, 6-locular with false septa, ovules many; style white, ca. 5 mm long, thick with a central canal; stigma 3, each bilobed forming a small stigmatic chamber. Fruits pendent, baccate, without core, indehiscent, 7.5-10 cm x 3-4 cm, black-purple, with fleshy succulent purple pulp. Seeds dull black, round-ovate, flat, 5-7 mm in diameter.
Common Names: Aloe Yucca, Dagger Plant, Spanish Bayonet, Spanish Dagger, Coastal Yucca, Dwarf Yucca
