142 LUTHER BURBANK 



highly improved varieties, on the best of land, 

 but without irrigation or special fertilization. 



Of course this growth would not be duplicated 

 on all soils or under all conditions, but even in 

 inferior soils the growth of the Opuntias is phe- 

 nomenal, and the amount of forage produced 

 each season is greatly in excess in weight of that 

 produced by any other forage plant, not except- 

 ing alfalfa. 



When the extraordinary weight of fruit that 

 is borne by some varieties is further taken into 

 consideration, it becomes evident that the new 

 spineless Opuntia is the most productive plant 

 ever cultivated. It is within the possibilities that 

 a field of Opuntias, under ideal conditions of cul- 

 tivation, might yield in new slabs and in fruit an 

 aggregate edible product approximating four or 

 five hundred tons to the acre. This has already 

 been attained in smaller areas. 



As to soil, the Opuntias grow everywhere. 

 They may be planted on rich level land, or on the 

 steepest and poorest rocky hillside, along old 

 river beds, and among rock piles. 



But it must not be inferred from this that the 

 plant is oblivious to good treatment. The growth 

 and succulence of the slabs are greatly increased 

 by good soil. Reasonable cultivation of the soil 

 is also of benefit, and, under semiarid conditions, 



