XXIII. NATURE'S SOIL-CONSERVING 

 OPERATIONS 



'* Behold this compost! behold it well! 

 Perhaps every mite has once formed part of a sick person — yet behold! 

 The grass of spring covers the prairies. . . 

 The summer growth is innocent and disdainful above all those strata of 



sour dead. . . . 

 Now I am terrified at the Earth! it is that calm and patient, 



It grows such sweet things out of such corruptions, 

 It turns harmless and stainless on its axis, with such endless successions of 



diseased corpses, 

 It distils such exquisite winds out of such infused fetor. 

 It renews with such unwitting looks its prodigal annual sumptuous crops, 

 It gives such divine materials to men, and accepts such leavings from tJiem 



at the last.'' 



— Walt Whitman {The Compost). 



Natiire's system of cropping is on a permanent basis. 

 Her soils do not "run out." She puts back into them regu- 

 larly all that she takes out of them, and a little more. All the 

 mineral substances go back to the soil whence they came, and 

 with them, in the humus, goes carbon that was derived from 

 the atmosphere. There is loss of some valuable soil material 

 through leaching and floods, but the gain is greater than the 

 loss, and the longer her crops are grown, the more fertile the 

 soil becomes. 



Nature holds the soil together by occupying it full}-. She 

 grows mainly permanent crops. They are always mixed 

 crops; and the mixture is so varied that there is always 

 something to grow in every situation. The soil is held with 

 roots, and the dead herbage is held by the tough stems of the 

 living; it is rapidly disintegrated and the mineral residue is 

 fed to the roots again. Thus the food supplies of her vast 

 population are used over and over, and between times of use, 

 are scrupulously hoarded. 



Nature practices tillage, and on a vast scale, but it is not 

 our sort of rapid and wasteful tillage. It is slow soil-mixing 



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