100 The Bulletin 



than of increasing it. Not only do the chemical analyses show that 

 there is a fairly liberal supply of potash in these soils, but in no case 

 do we find any marked increases in yield due to its use, and frequently 

 the yield is actually reduced. Generally it certainly would give better 

 imniediate returns and would be far more beneficial to eliminate potash 

 altogether for general farm crops, and put the money into an additional 

 supply of phosphoric acid. Potash, however, can be applied with profit 

 to tobacco and very probably to Irish potatoes on most of the Piedmont 

 soils. 



LIME. 



The results on all the soils, with the exception of Field C at the Ire- 

 dell farm where several crops of cowpeas had been previously plowed 

 into the soil, do not indicate that the Piedmont soils in their present 

 condition are particularly benefited by applications of lime, except for 

 leguminous crops like crimson clover, vetch, and red clover, and for soils 

 on which these have been plowed into them. Chemical examination 

 does not show them to be strongly acid or generally lacking in lime. 

 The soils thus far examined in the Piedmont Section show those of the 

 Iredell, Mecklenburg and Congaree series in the order named to con- 

 tain the highest percentage of lime. 



CROP EOTATIOlSr NECESSAKY FOR A PERMANENT SYSTEM OF AGRICTTLTUEE. 



It is the duty of every owner of agricultural land in this or any 

 other section of' the State to follow methods of crop rotation and ferti- 

 lization which shall maintain the producing power of the fertile soils, 

 and which shall build up that of the poorer ones. Our methods of fann- 

 ing should be such that the soils would become more_ productive year 

 by year. The one great purpose in the present investigation of North 

 Carolina soils as outlined in the beginning of this report, is to deteraiine 

 the most economical methods of fertilizing the various soil types, which, 

 when applied in conjunction with proper crop rotation, will increase 

 the producing power and thereby establish a better system of agricul- 

 ture in the Piedmont Eegion of the State. 



"We have experimental work in progress in this section which has this 

 end in view. All of the results thus far secured in the experiments on 

 the outlying fields and a resume of all the results from 1902 through 

 J909 with cotton, corn and cowpeas at the two experimental f arms m 

 the Piedmont Section are presented in Tables I-X of this Bulletin. 

 From the information at hand we are able to recommend methods which 

 if followed on the main soil types of the Piedmont Section of the State 

 will come nearer maintaining their productivity than the methods more 

 commonly now in practice. 



Such a system of management must first of all include the applica- 

 tion of phosphoric acid. In addition, it must include either the use of 

 large quantities of farm manures or the turning under of leguminous 

 crops. The organic matter in the case of the greater part of the culti- 

 vated soils of the Piedmont Section must be increased before maximum 

 grain crops can be produced at a profit. With this purpose in view the 

 following rotations are recommended : 



