14 BULLETIN 728, U. S. DEPARTMENT OF AGRICULTURE. 



It thus appears that most of the species here listed, if used up, 

 are not likely to return. Fortunately, the most valuable species 

 ( Yucca data and Yucca glauca) may be expected to recover after 

 cutting, the former slowly and the latter more rapidly, especially 

 if the plants are not cut too close and are given an opportunity to 

 grow. 



It should be clearly understood that the supply of this emergency 

 feed is not by any means inexhaustible; in fact, on many ranches it 

 is scarce or very limited in amount; also that natural renewal is slow 

 with the best species and improbable with others, while it is reason- 

 ably rapid with but one species {Yucca glauca). Present knowledge 

 of the plants indicates that they should be used for emergency feed 

 only. They should be allowed to store a supply of feed, in what 

 might be called a natural or living silo during the favorable growing 

 seasons, that may be used when the years of low rainfall and poor 

 grass come — years that are sure to come when the dry part of the 

 precipitation cycle arrives, as it does every 10 or 12 years. 



QUALITY OF THE FEED. 



In 1896 an analysis of sotol was published by the New Mexico 

 Agricultural Experiment Station in Bulletin No. 17, but none of tne 

 other plants here treated were then thought of or used as feed, ex- 

 cept as cattle occasionally chewed a few of the dry leaves. 1 In 1903 

 some ash analyses of three of the species listed here were published 

 by the same station in Bulletin No. 44. In October, 1917, a press 

 bulletin with analyses of sotol and soap weed was sent out by the 

 same station, with comparative data for other more common feeds. 

 On February 1, 1918, the Arizona Agricultural Experiment Station 

 published two analyses of Yucca data. 2 



The Bureau of Chemistry, United States Department of Agricul- 

 ture, has been called upon to make analyses of a number of these 

 plants at different times. The details of all are presented in Table 

 I, all records being computed on a water-free basis. Along with 

 these are some analyses of a few of the better known feeds, with 

 which they may be compared. None of the ordinary feeds are 

 exactly like these desert shrubs. They contain less water than 

 most fresh feeds and considerably more than most dry hays. The 

 average water content of four samples of soap weed when first pre- 

 pared was 65.86, while for five samples of sotol the average water 

 content was 60.23 per cent. s 



1 In 1898 the Texas Agricultural Experiment Station published in Bulletin No. 44 an analysis of 

 satol from Bull's ranch, no further data being given. This is possibly a misprint for sotol. 



2 Thornber, J. J. Soap weed or palmilla ( Yucca data) as emergency forage. Ariz. Agr. Exp. Sta., 

 Timely Hints for Farmers 135, 7 p., 1 fig. 1918. 



A preliminary report on some feeding experiments with soap weed and sotol is made in Press Bulletin 

 308 of the New Mexico Agricultural Experiment Station. 



