ARID AGRICULTURE. 105 



is most needed, that is, not just at the base of 

 the tree, but some little distance out and sur- 

 rounding the tree. Under this area are the small 

 roots that absorb water and feed the tree. Un- 

 it-- cultivation is practiced in the basins, where 

 the ground contains much clay, it is apt to bake 

 badly, and crack. These cracks may even ex- 

 tend through the banks and the basin may need 

 some attention to keep it from leaking. The 

 main objection to this method lies in the yerv 

 large first cost of preparing the land. The ac- 

 tual labor of irrigating is very small, although it 

 is necessary to let out the water from one basin 

 when it has stood long enough and turn it into 

 the next one, until all are irrigated. 



METHODS The furrow method, or one of the sub-irriga- 



sorcs ilon methods, is best suited to all heavy soils 



which are not so dense thev will not absorb 

 water readily, as there is more crusting of the 

 surface and cracking when they are flooded. 

 With the furrow methods it is also easy to mulch 

 either the whole surface, or that part lying be- 

 tween the furrows. Seepage or percolation 

 through the soil in the furrow method is aided 

 by leaving the surface of the furrow rough, with 

 clods in it, so that the water flows down slowly 

 and has plenty of time to soak to the roots of the 

 plants. 



