8 Irrigation and Drainage, 



and glistening in the sun, and which drifted as badly 

 as much of apparently similar land in Wisconsin, and 

 yet on these coarse sands wheat was being harvested 

 which would give larger yields than would be expected 

 on such lands in Wisconsin with a summer rainfall 

 of not less than ten inches. But here the crop had 

 stood and matured from early May until the end of 

 July without irrigation and without rain. One is led 

 to question whether it may not be true that, under 

 the stress of such arid conditions of both atmosphere 

 and soil, plants of some kinds may develop a texture 

 of a closer nature, with fewer and smaller breathing 

 pores, and thus reduce the loss of moisture through 

 their surfaces much below what is normal to the same 

 species under more humid conditions of soil and atmos- 

 phere. Such a question could, of course, readily be 

 settled by a proper comparative study of tissues de- 

 veloped under the two conditions ; but, so far as we 

 know, it has not yet been done. It should be said, 

 however, in this connection, that the seemingly greater 

 service of water to which reference is here made may 

 be more apparent than real. The climate of the region 

 being warm, and wheat being sown from the begin- 

 ning of the rainy season in November until the end 

 of January, there is much time for the crop to germi- 

 nate, and to get its root system thoroughly established 

 in the ground, and to have made a very considerable 

 growth, before the close of the rainy season early in 

 May. There are left, then, only the months of May 

 and June during which the crop must complete its 

 growth without rain. It is true that this is a long 



