34 Tub Bulletin. > 



In the use of the rock, not only is the yield being increased as 

 rapidly, but the soil is being enriched in phosphoric acid four times 

 as fast. The practice of mixing rock phosphate with manure as it | 

 accumulates in the stable is certainly commendable. We advise the 

 addition of 75 to 100 pounds to each ton of manure for the soils 

 of this section. Another method of using the rock phosphate is to 

 apply it to clover sod or a green catch crop. In this case we would | 

 recommend an application of SOO to 1,000 pounds per acre every '' 

 three or four years. 



NITROGEN. I 



I 



Most of our tilled mountain soils are deficient in organic matter, 

 and therefore lack nitrogen, as organic matter is the principal source 

 of nitrogen in the soil. This source of supply is not sufficient as is 

 sho-wn by the plat results. Other than organic matter there are three ] 

 sources from which to obtain nitrogen: commercial fertilizers, farm 

 manure, and the free nitrogen of the air. 



There are many nitrogenous materials used as fertilizers, but | 

 they are all expensive. Especially is this true for the moimtains, ' 

 since the general farm crops are heavy feeders on nitrogen. In the • 

 eastern part of the State where cotton is the leading crop commercial 

 carriers of nitrogen can be used with profit. Where grain and 

 grasses are grown chiefly, however, other sources must be depended 

 upon. Stable manure furnishes one of the most desirable sources, 

 as there are large amounts of organic matter in it as well as nitrogen, 

 and at the same time considerable quantities of phosphoric acid and 

 potash. Still, it is not a well-balanced fertilizer for these soils unless 

 fortified with additional phosphoric acid. Valuable as it is, however, 

 the supply of organic matter and nitrogen in the soils throughout 

 this section can not be built up through the use of manure alone, 

 because in the production and handling of manure there is a great 

 loss of the element nitrogen. 



The only other available source is that contained in the air. Here 

 we find the supply which must be largely depended upon in the 

 permanent increase of the supply of this element in the soils of the 

 Mountain section. Most crops, including the grains and grasses, are 

 unable to draw upon the inexhaustible supply, but there is a large 

 class known as legumes which have this power. The clovers, peas 

 and beans, as is commonly known, are legumes. They furnish an 

 economical means of maintaining and even upbuilding the supply 

 of this most expensive element of plant food in our soils. It has 

 truthfully been said of them that ''They not only feed themselves, 

 but pay for the privilege," meaning that they not only secure nitro- 

 gen for their own growth but at the same time furnish a profitable 

 crop. 



