THE VOICE OF THE DESERT 



142 



anybody, since the same thing is true of domestic animals. 

 It is a lot easier to keep a chicken or a canary in New Eng- 

 land, where neither is native, than it would be to keep a 

 chickadee, however many hundreds of the latter may be 

 flourishing in the neighborhood. But what is to some ex- 

 tent true of many wild plants is especially true of the 

 desert species. Beginning to live in the desert is, if any- 

 thing, even more difficult than living there once you have 

 got started. Many kinds of plants as well as animals can do 

 it, but they have to do it in their own way. 



As usual the number one difficulty for a chance seedling 

 is created by the shortage of water except during the short 

 wet periods. Most desert plants produce their seed at the 

 end of a rainy season which is followed by a long drought. 

 Obviously if the seeds fell to the ground and germinated 

 in the possibly still damp earth they would, shortly after, 

 be burned up. Some method had to be devised to prevent 

 them from behaving in any such imprudent fashion. In 

 the California and the Mexican deserts the problem is rel- 

 atively simple because there is only one wet season, that of 

 winter rains in the one and of summer rains in the other. 

 But in southern Arizona it is complicated still further by 

 the fact that there are two — in midsummer and midwin- 

 ter. And since some plants do most of their growing after 

 the winter rains and some after the summer, they have to 

 be careful not to come up during the wrong wet period. 



One way of getting around this difficulty is simply to re- 

 fuse to come up at all except after one year (or perhaps 

 two or three years ) has passed. And that can be arranged 

 by taking advantage of a trick which pharmacists have 

 recently learned to play when they want to delay the ac- 

 tion of some pill for a certain number of hours after it is 



