Botanist Howard Scott Gentry[2] first collected the species and mentioned it in print, noting the differences between this population and the closely related species Y. grandiflora H. S. Gentry and Y. arizonica McKelvey (sic, = Yucca baccata var.

[3] The epithet declinata refers to the fact that this is the only known species of Yucca in which the flowering stalk is oriented horizontally.

Flowering stalk is up to 130 cm m long, glabrous, usually perpendicular to the main stem.

Fruit oblong, tapering at base, 15–20 cm long, not splitting apart when ripe.

The species occurs in open woodlands and scrublands on volcanic and limestone soils.