mostly erect clusters of large, waxy, whitish, and usually pendent 

 flowers are striking in appearance. The flowers are perfect (i. e., con- 

 taining both male and female parts) and the evident stalk (style) 

 of the seed-producing organ (ovary) is stout. The rather thickish 

 perianth parts are separate or only slightly united, the inner three 

 usually being white or cream-colored and more delicate in texture 

 than the outer three, which are sometimes tinged with purple or 

 pink ; the six stamens are inserted at the base. The fruit is a three- 

 celled or imperfectly six-celled capsule, either dry or somewhat fleshy 

 and berrylike. Soaptree yucca is distinguished among its treelike 

 sister species of the United States largely by having the flower 

 cluster raised on a conspicuously long (about 3 to 7 feet), naked 

 stalk, by its slender, thread-fringed leaves, pale or white on the 

 margins, and by its dry, erect, splitting (dehiscent) fruit. 



Yucca flowers are not self-pollinated, but depend upon the agency 

 of certain small moths (Tegeticula spp., syn. Prowifoa spp.) ; in fact, 

 both the yuccas and the moths are interdependent for perpetuation of 

 their respective species. 6 7 T. alba (syn. Pronuba alba} pollinates 

 Yucca elata and datil (Y. baecata}.* 7 The female moth, working at 

 night, collects pollen from one flower, then flies to another, lays her 

 eggs in the seed-producing organ, and "in a manner which corre- 

 sponds to actions full of purpose and deliberation climbs to the style 

 (i. e., the stalk of the pistil, or seed-producing organ) and thrusts 

 the pollen ball down the stigmatic tube." 8 



Small soap weed (Y. glau'ca), also called soap weed yucca, is a 

 short-stalked, narrow-leaved species with small flowers about 1% 

 inches long. The datil, meaning little date, often called banana 

 yucca, is similar, but the leaves are much broader and more rigid 

 and the flowers larger (2 to 3 inches long) ; its somewhat banana- 

 like fruits have a sweet, edible pulp surrounding the seeds. The 

 Datil National Forest of New Mexico was named after this species. 

 The flower clusters of both of the above species are palatable to 

 cattle and sheep, and the young leaves are eaten to some extent, 

 especially during drought. Cattle and deer, attracted by their suc- 

 culence and palatable juices, sometimes pull the leaves and chew 

 the lower portions of these plants. These species lack the pulpy 

 stem of soaptree yucca, being much inferior as chopped emergency 

 feed. The Indians used the fruit of the datil as food; the roots of 

 both of the above species as soap ; and the leaves as fiber in weaving. 



Trelease, W. FURTHER STUDIES OP YUCCAS AND THEIR POLLINATION. Mo. Bot. Gard. 

 Ann. Kept. 4: [181]-226, illus. 1893. 



1 Comstock, J. H. AN INTRODUCTION TO ENTOMOLOGY. Rev., 1,044 pp., illus. Ithaca, 

 N. Y. 1933. 



8 Jepson, W. L. A MANUAL OF THE FLOWERING PLANTS OF CALIFORNIA. 1,238 pp., illus. 

 Berkeley, Calif. [1925.] 



