36 The Bulletin 



how to supply plant-food requirements. 



For Nitrogen. — Soils that show a need for applications of nitrogen 

 or ammonia can usually be considered as deficient in organic matter, 

 and when the organic matter is high one can generally figiire on the 

 soil being relatively well supplied with this constituent. 



Analyses and field results have shown that the soils of the county are 

 generally low in nitrogen. One of the main problems, therefore, for 

 the farmers is to supply this constituent in fairly liberal quantities to 

 the soil, and do it as cheaply as possible. The chief means that must 

 be used in supplying the nitrogen will be by the growing of suitable 

 leguminous crops, properly inoculated, on the land and turning all or 

 part of these into the soil. By such a plan not only would the supply 

 of this constituent be increased, but the physical properties of the soil 

 would be greatly improved by the addition of the organic matter to 

 such an extent that baking would be greatly reduced after rains and 

 plowing made easier and much more satisfactory. 



Other materials that may be depended upon to supply the needs of 

 the soils are farm manures and commercial fertilizers. The commer- 

 cial materials that carry moderate or high percentages of nitrogen are 

 usually expensive. It is frequently difficult to have low-priced prod- 

 ucts like corn pay as well for other than moderate applications of farm 

 manures. Of course, when corn is selling at as high prices as it is at 

 the present time much larger amounts, when properly used, may be 

 added to an advantage. Where a crop like cotton is grown and the 

 prices secured for the seed and lint are fair, or high, farmers will 

 find, usually, the use of commercial forms of nitrogen in proper 

 amounts may be used profitably, provided they are combined with 

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

 any particular soil. Where grains and grasses are grown, mainly, other 

 sources than the commercial ones will generally have to be depended 

 upon to a large extent. Barnyard manure furnishes one of the most 

 desirable sources of this constituent, as there are combined with it 

 large amounts of organic matter and moderate amounts of phosphoric 

 acid and potash. This material, however, is not very well balanced in 

 the plant-food constituents it contains to meet the requirements of the 

 soils of the county. It Avill, therefore, have to be supplemented by ma- 

 terials carrying the required fertilizing constituents needed by the soil, 

 the chief of which are phosphoric acid and nitrogen. The nitrogen 

 will be provided by the manure if it has been saved properly and the 

 phosphoric acid by adding to it acid phosphate or some other commer- 

 cial carrier of this constituent. As valuable as barnyard manure may 

 be, it cannot be depended upon by farmers, generally, to keep up the 

 organic matter and nitrogen supply of their soils, as the amount of 

 manure produced on the farm is relatively small as compared with the 

 acreage geiierall}' devoted to the growing of crops. 



