CACTUS AND GREASE-WOOD 



137 



Many of the desert growths have it. Perhaps 

 the most notable example of it is the wild gourd. 

 This is little more than an enormous tap root 

 that spreads out turnip-shaped and is in size 

 often as large around as a man's body. It holds 

 water in its pulpy tissue for months at a time, and 

 while almost everything above ground is parched 

 and dying the vines and leaves of the gourd, 

 fed from the reservoir below, will go on grow- 

 ing and the flowers continue blooming with the 

 most unruffled serenity. In the Sonora deserts 

 there is a cactus or a bush (its name I have never 

 heard) growing from a root that looks almost like 

 a hornet's nest. This root is half-wood, half- 

 vegetable, and is again a water reservoir like the 

 root of the gourd. 



But there are reservoirs above ground quite 

 as interesting as those below. The tall fluted 

 column of the sahuaro, sometimes fifty feet 

 high, is little more than an upright cistern for 

 holding moisture. Its support within is a se- 

 ries of sticks arranged in cylindrical form and 

 held together by some fibre, some tissue, and a 

 great deal of saturated pulp. Drive a stick 

 into it after a rain and it will run sap almost 

 like the maguey from which the Indians distill 

 mescal. All the cacti conserve water in their 



Storage 

 reservoirs 

 below 

 ground. 



Reservoirs 

 above 



