26 The Bulletin 



ing of all or part of these into the soil. By such a plan not only would 

 the nitrogen be increased, hut the physical properties of the soil would 

 be greatly improved by the addition of the organic matter. 



Other materials that may be depended upon are commercial fertilizers 

 and farm manures. The commercial materials carrying nitrogen are 

 usually quite exjiensive. It is frequently difficult to have low^-priced 

 products like corn pay well for other than moderate applications of com- 

 mercial forms of nitrogen. Where cotton is grown and the prices secured 

 are fairly good for the lint, farmers may usually use commercial forms 

 of nitrogen and have them prove profitable if they are properly combined 

 with other materials that will supply the other needs of the crop grown 

 on their particular soils. 



Where grains and grasses are the principal crops, other sources than 

 the commercial ones will have to be depended upon usually. Barnyard 

 manure furnishes one of the most desirable sources of this constituent, as 

 there are contained large amounts of organic matter with the nitrogen 

 and moderate amounts of phosphoric acid and potash. This material, how- 

 ever, is not a well balanced fertilizer for the soils of the county, and it 

 will therefore have to be supplemented by materials carrying the required 

 fertilizing constituents needed by the soils of the county, the chief of 

 which, as indicated above, is phosphoric acid for the Cecil soils after 

 nitrogen has been provided. As valuable as this material is, the supply 

 of organic matter and nitrogen cannot be kept up by having to depend 

 upon the manure produced on the farm, as this amount is relatively very 

 small as compared with the acreage usually devoted to the growing of 

 crops. 



Phosphoric Acid. — This constituent is very low in the soils of the 

 county. With the farmer it is necessary for him, in order that his profits 

 may be greatest, to use the source of phosphoric acid that is going to give 

 the highest net returns. Taking everything into consideration, the two 

 commercial forms that will have to be depended upon at the present time 

 are acid phosphate and basic slag. Of course, there wdll be added to the 

 soil a considerable amount of phosphoric acid when manure, cotton-seed 

 meal, soy-bean meal, or ground bone is used alone or when such mate- 

 rials as tankage and fish-scrap are added to the soil. Where large 

 amounts of organic matter are being turned into the soil in many cases 

 it will probably be profitable to add finely ground phosphate rock. The 

 organic matter in rotting will tend to bring into an available form some 

 of the phosphoric acid contained in this material. Again, a good plan 

 in many cases would be to add this material to manure in the stable as 

 it is being formed, using at the rate of one to two pounds per day broad- 

 cast over the manure, making the applications about twice per week. 



Potash. — With the soils of this county, as well as with Piedmont 

 soils generally, the least important constituent of the main plant-foods 

 has been found to be potash. Iredell clay loam has been found to be 

 lower in this constituent than any other type of soil found in the county. 



