THE SOIL 65 



pulverized if the real benefit of cultivation is to 

 be obtained. I have had men from the city in 

 the orchard when we were "dust mulching" 

 and they expressed surprise that such work 

 could conserve moisture. "Why," they would 

 say, "you are simply turning that dirt over and 

 over and causing it to become drier and drier 

 every minute. You are helping your moisture 

 to escape instead of conserving it." I admit 

 that — on the surface — it did look like that. But 

 under the surface there was a different story. 



You may go into a dust mulched orchard in 

 the driest time in summer and with the toe of 

 your shoe you can scratch down to moist earth, 

 only a few inches under the surface. Go ten 

 feet away from that mulched surface and dig 

 in the "big road" where the earth is hard and 

 baked and you may dig for half a day without 

 finding any trace of moisture. 



The layer of dust acts as an impervious stra- 

 tum through which the moisture of the soil can 

 not escape. Most soils possess what we call 

 capillarity. That means that they can draw 

 moisture from deep sources by the action of the 

 tiny spaces which exist between the individual 

 soil particles. If you will take a broken ther- 

 mometer tube and insert it in a dish of water 

 you will see that the water rises in the hair-like 

 (capillary) chamber of the tube. This is one 

 of the irresistible forces of nature and plays a 



