HUMUS 



THUS far, we have considered only the plant food elements con- 

 tained in manure. Manure has another value of greater impor- 

 tance which, if thoroughly appreciated by the farmer, would prompt 

 him to make stock-raising a prominent feature and cause him to preserve 

 and utilize every atom of everything which can be construed as manure, 

 for it is the foundation of the yeast of the soil. It is the organic sub- 

 stance which is finally resolved into humus. 



Value of Humus 



Humus is just as necessary to make soil fertile as water is to make lime 

 and sand into plaster. Soil which is barren of live humus is as unpro- 

 ductive as pure sand. The value of humus is apparent, but the chem- 

 istry of its component parts is not thoroughly understood. 



We know, however, that it is the portion of organic matter found in 

 the soil which is in a partly-rotted conditon. 



We know that it supplies nitrogenous plant food and combines with 

 phosphorous, potash and other fertilizing elements, making them avail- 

 able and effective. 



We know that it furnishes the food for niter-forming bacteria which 

 convert it into nitrates, an available form of organic nitrogen. 



We know that it improves the phyiscal condition of the soil by mak- 

 ing it mellow and friable and gives it permeability and substance. It 

 also assists in the absorption and retention of moisture, prevents pud- 

 dling, baking and cracking and renders light sandy soils productive 

 and clay soils tillable. 



It influences the temperature of the soil to a marked degree. In fact, 

 it is the one great substance which cannot be dispensed with in our 

 efforts to maintain the fertility of the soil. 



Humus must be renewed from time to time, for it becomes worthless 

 in soil which has been repeatedly cropped with the same crop or like 

 crops. It can be supplied, renewed and kept active by the application 

 of barnyard manure, green crops plowed under and rotation of crops. 

 Intensive methods of tillage are also factors in keeping humus active. 

 Soils may be rich in potash, phosphorous and other inorganic elements 

 and be abandoned as "worn out" when, in fact, they need only humus to 

 make them very productive. It must be remembered, however, that 

 HUMUS is practically worthless in unventilated, water-logged and 

 sour soils. Such soils need lime and drainage. 



Benefits of Manure and Crop Rotation 



Manure is the foundation of successful agriculture and will be until 

 the laws governing plant life and the formation of plant food compounds 

 are changed. 



