ROOTS AND TUBERS 



199 



saltbiish, introduced into California and Arizona, will produce 15 to 

 20 tons of green forage per acre under favorable conditions, or 3 to 5 

 tons of coarse hay which has about the same digestibility as oat 

 hay. 



Cacti.— During periods of drought the cacti, especially prickly 

 pears, are a boon to stockmen of the arid western regions. Because 

 of their peculiar structure and habits, cacti can survive long droughts, 

 tho they make little growth at such times. Prickly pear cacti may be 

 fed where they stand by first singeing otf the spines with a gasoline 



Fig. 57. — Singeing Prickly Pear with a Gasoline Torch 



After the spines liave been singed off cattle can feed on prickly pear without 

 harm. Another method is to cut the cacti and run them thru machines which 

 chop them, rendering the spines comparatively harmless. (From U. S. Depart- 

 ment of Agriculture.) 



torch, or they may be gathered and run thru machines which chop 

 them in such a manner that the spines are comparatively harmless. 

 Cacti grow but slowly on the range, and can usually be harvested but 

 once in 5 years, even under favorable conditions. 



Prickly pear cacti contain about 16.5 per ct. dry matter, being less 

 watery than roots, and cane cacti contain somewhat more dry matter. 

 Since they are low in protein, all the cacti should be fed with a pro- 

 tein-rich concentrate or roughage. Cacti alone do not maintain stock. 

 Tho desert cattle sometimes subsist on them for 3 months of the year, 



