ABSTRACT
About forty species of the genus Yucca grow in the warmer parts of North America, and a few species are hardy in colder climates. These members of the family Agavaceae are extensively cultivated, particularly in the South. The plants, with their stiff, usually swordshaped leaves, may or may not have an erect, central stem. Many have descriptive common names that are much more widely recognized than their botanical designations. Yucca aloifolia L. is called Spanish-bayonet or dagger plant; Y brevifolia Engelm. is the wellknown Joshua tree; Y glauca Nutt. is referred to as soapweed; Y whipplei Torr. is our-Lord's-candle.1 Yucca schidigera Roezl. ex Ortiges, Mohave yucca, is also common in the herb trade.
