14 MISCELLANEOUS PAPERS. 



RELATIVE VALUE OF THE THREE GROUPS OF CACTI. 



On account of several practical considerations the prickly pears 

 are of much more value than either of the other two groups. They 

 are more numerous in the wdld state, they adapt themselves to culti- 

 vation more readily, make a more rapid growth, and are more readily 

 propagated from cuttings, all of wliich are of ^"ital importance in the 

 economic use and handling of the crop. Practically all of the Mex- 

 ican prickly pears are fed to stock to a greater or less extent, espe- 

 cially those gi'o\\'ing where fodder is the most scarce, but there is only 

 one cj'lindrical-jointed species (Opuntia imhricata) wliich is used to 

 any appreciable extent. The experience of the writers has shown that 

 Cereus giganteus is readily eaten by cattle when chopped up, but 

 they know of no actual feeding having been conducted %\-ith it on 

 any commercial scale. ^Ir. C. R. Orcutt states that Echinocactus 

 orcuttii, which is tyj^ical of a considerable group of species, is occa- 

 sionally fed in Lower California. It is only in rare instances, how- 

 ever, that any great quantity of feed can be secured from cacti, out- 

 side of the genus Opuntia, and the greater part of the feed in this 

 genus is produced by the flat-jointed forms. There are about five 

 species in the cylindrical-jointed group which have been fed ^^'ith 

 some success. Opuntia imhricata, from ^lexico, has been referred to, 

 and in various writings the use of Opuntia arhorescens, Opuntia spi- 

 nosior, and Opuntia fulgida are mentioned. To these should be 

 added Opuntia prolifera from the coastal region of southern Cali- 

 fornia. These species constitute, ^^'ithout doubt, the best of the 

 cylindrical-jointed group, and when extent of territory covered, suc- 

 culence, and ease of propagation are taken into consideration Opuntia 

 fulgida and Opuntia imhricata are probably the most valuable of 

 this group. Opuntia arhorescens has a decidedlj^ valuable character- 

 istic in that it extends farther to the north than any of the other 

 economic species of any of the groups, and it is fed to a considerable 

 extent in localities from southern Colorado southward. 



The use of these species, however, and, in fact, the extended use of 

 nearl}^ all the native species of this country and Mexico, presupposes 

 artificial preparation. In dry seasons in southern Arizona, cattle feed 

 upon the pendent bunches of fruits of the choUa {Opuntia fulgida), 

 but it is done at a great sacrifice of comfort. The Texas pear 

 (Opuntia lindJieinneri) is grazed to a considerable extent by cattle, 

 sheep, and goats \vithout an}^ preparation whatever, and even such 

 thorny forms as cardon, shown in Plate I, are grazed by cattle in 

 extreme cases. '^ 



a For fm-ther discussion, see Bulletin 74 of the Bureau of Plant Industry. 



102—1 



