Yucca angustissima

Yucca angustissima, the narrowleaf yucca, is a plant in the family Agavaceae, known as the "narrow-leaved yucca." It is native to Arizona, New Mexico, Colorado and Utah, but grown elsewhere as an ornamental. Yucca angustissima is a low-lying species forming colonies of basal rosettes up to 3 m (10 feet) in diameter. Leaves are long and thin, up to 150 cm long but rarely more than 2 cm across. Flowers are white to cream or greenish-white, pendant, borne in racemes on stalks up to 2 m (7 feet) tall. Fruit is a dry capsule with black seeds. Yucca angustissima is relatively abundant, and although it has local threats, its population appears to be stable overall....read more on Wikipedia.