B157 

 (leaf 2) 



feeding in moderation during the first few days. Otherwise, this 

 feed has a very good effect upon livestock. Experiments show that 

 cattle can be fattened if fed freely on a mixture of 1 pound of meal 

 to 15 pounds of "soapweed." Economically, ho\yever, the use of this 

 plant should be restricted to drought emergencies. The feeding of 

 chopped soaptree yucca in 1918 saved many thousands of south- 

 western cattle from starvation. 3 Fortunately, this plant is not 

 killed by cutting, as it sprouts readily from the roots. Growth, how- 

 ever, is very slow and a rotation of from 10 to 15 years is necessary 

 to insure a perpetual supply. 2 3 



The roots of soaptree yucca are used locally (under the name 

 amole) as soap by both Indians and white men. This use is reflected 

 in the common names soaptree yucca and soapweed. The soap has 

 a particularly high reputation for shampooing the hair and, as such, 

 is marketed commercially on a limited scale. The Indians also use 

 the remarkably tough leaf fibers in making baskets, ropes, and mats. 

 During the World War emergency, the fiber was used as a substitute 

 for jute in the manufacture of bagging, but has never attained com- 

 mercial importance in peace times. 



Soaptree yucca has a local utility in checking wind erosion and 

 also is esteemed for the shad.e which it provides in regions where 

 shade is at a premium. 4 5 It is a valuable and beautiful ornamental 

 plant, especially on ranches where the water supply is not sufficient 

 to enable introduced shade trees and shrubs to survive. The wood, 

 as in other arborescent yuccas, is light and flexible, yet tough and 

 porous hence very desirable as splints for broken limbs. Campbell 

 and Keller 5 report that mature Yucca elata plants show an annual 

 growth of one-half of an inch to two inches, depending largely on 

 the amount of summer rainfall, the average annual growth being 

 about an inch. These authors also observed the growth and long- 

 evity of the leaves of this species, and give a list of the insects, rep- 

 tiles, and mammals associated with it. 



The yuccas, numbering about 30 species, are confined to North and 

 Central America, Bermuda, and the West Indies, most of them 

 being native to the arid regions of the Southwest and the tablelands 

 of Mexico. Together with a number of other genera belonging to 

 the lily family (Liliaceae), the yuccas are distinctive in this largely 

 herbaceous family because of their frequent arborescent habit of 

 growth, large size, and the bold, rather palmlike effect which they 

 lend to the landscape. Although some of the species of yucca are 

 acaulescent, i. e., do not produce an erect stem except for the flower 

 stalk, the majority develop a trunk, often treelike, which may be 

 branched or unbranched. The long, stiff, sword-shaped or linear, 

 needle-pointed leaves, which are usually fiber-bearing and some- 

 times toothed on the margins, are characteristic of this genus; the 

 leaves form a dense basal tuft in the stemless species or clothe the 

 trunk or ends of the branches in the arborescent forms. The huge, 



* Dayton W A. IMPORTANT WESTERN BROWSE PLANTS. U. S. Dept. Agr. Misc. Pub. 

 101, 214 pp., illus. 1931. 



6 Campbell, R. S., and Keller, J. G. GROWTH AND REPRODUCTION OF YUCCA ELATA. 

 Ecology 13: 364-374, illus. 1932. 



