THE VOICE OF THE DESERT 



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one. Like the saguaro it takes up water when it can get it, 

 but instead of storing what has been taken in a massive 

 stem, it stores it underground where loss by evaporation 

 must be even less. And when the time comes to bloom in 

 the midst of an absolute drought, it is independent of pre- 

 vailing conditions. It simply draws upon its private stock. 

 Nor does it, the poet notwithstanding, "waste its sweet- 

 ness on the desert air." When a blossom is fragrant that 

 usually means that it needs some insect to polhnate it. 

 When the blossom is white and opens at night that means 

 that some night-flying insect is being invited. And you 

 may be sure that it will accept the invitation. Before sum- 

 mer is over many of the stems of the queen will bear larg- 

 ish, pulpy red "pears" much like those of the commonest 

 cactus. 



If any reader happens to wonder just how well all the 

 devices for economizing water really work, how efficient 

 they really are, some very good answers can be given. We 

 know that desert plants survive and flourish. But how 

 much do their special mechanisms contribute to this sur- 

 vival? It happens that studies have been made on the 

 saguaro, and those which compare it with the date palm, 

 cultivated commercially in the saguaro belt, are especially 

 impressive. 



The date palm is not especially good at economizing 

 water. Where it grows in the old-world deserts, in the 

 Sahara for example, it can do so only where there is abun- 

 dant subsurface moisture, and when natives want to estab- 

 lish a new grove they not only have to plant the young 

 trees deep, but also to water them until the roots have had 

 time to grow much deeper still. Here in Arizona, where 

 such abundant subsurface water is not available, even the 



