The Bulletin 35 



Applications of potash have not generally been found to be absolutely 

 essential for general crops, such as small grains, corn and cotton, to be 

 assured of good yields. It is more probable that for such crops as 

 tobacco, potatoes, and legumes applications of this constituent when 

 prices are normal will prove more profitable; especially is this so when 

 the soils are low in organic matter; notwithstanding, good crops might 

 be grown without it. In experiments on the Alamance Silt Loam, near 

 Monroe, fairly low in organic matter, it has been found that the use 

 of potash when available at normal prices has increased the yields of 

 mixtures of oat-and-vetch hay and seed cotton in sufficient amounts to 

 justify its use. It is believed that with the organic-matter supply ma- 

 terially increased in this soil, as well as other types occurring in the 

 county, the necessity for applications of potash may not be found to 

 be so great in order to secure good returns. 



The phosphoric-acid content in the Georgeville Silt Loam, George- 

 ville Silty Clay Loam, Alamance Slate Loam, Iredell Loam, Congaree 

 Silt Loam, and the Alamance Gravelly Silt Loam is sufficiently high 

 to lead to the belief that when these soils are handled in such a way 

 as to embrace in them a considerable amount of organic matter the 

 necessity for the use of applications of materials carrying phosphoric 

 acid will not be so pressing; particularly is this so with the George- 

 ville Silty Clay Loam, and Alamance Slate Loam. In the experi- 

 ments in Mecklenburg County on the Iredell Loam type of soil it was 

 found that applications of phosphoric acid did not increase the yield 

 at all. It is probable that because of the high content of phosphoric 

 acid in this type in this county this same condition may exist with 

 soils of the Iredell Loam type to a more or less extent. 



Judging from the chemical analyses of the soils of the different 

 types found in the county as well as from such other information as we 

 have with reference to them, it is judged that in a general way, with 

 the exceptions noted, nitrogen and phosphoric acid are the two con- 

 trolling plant-food constituents in plant production. It will be seen, 

 then, that the field results in a general way are borne out by chemical 

 analyses of the soils. This is not ahvays true, as has frequently been 

 found the case with some of the eastern soils. The incorporation of 

 organic matter, too, with practically all of the soils of the county low 

 in organic matter is of the highest importance, as, generally speaking, 

 the percentage of this material in the soils is relatively low. When 

 leguminous crops and other cover crops are gro\\ai and plowed into 

 the soil to increase the organic-matter supply already present it will be 

 found, in all probability, in most cases that a fairly liberal use of lime 

 will be essential for the largest and most profitable returns. Our ex- 

 periments in this section indicate that lime is essential for best returns 

 where a proper system of crop rotation is practiced and organic matter 

 is constantly being plowed into the soil. 



