56 FIELD CROPS 



To be reasonably sure of success, corn land must be suffi- 

 ciently well drained to allow a free circulation of air in the 

 soil to a depth of from 2 to 3 feet, must have enough plant 

 food available for the production of ordinary field crops, 

 and must be situated where there is a sufficient period of time 

 free from frost to allow the crop to mature. A higher aver- 

 age temperature must prevail than is necessary for some of 

 the small grain and grass crops. The soil must be compact 

 enough to retain moisture, yet should be fine and mellow 

 enough so that the roots may easily penetrate it. 



The com plant in its growth uses large amounts of mois- 

 ture. Corn can hardly be termed a dry-land crop, as it must 

 have a reasonable supply of moisture to succeed, but it can 

 be carried over periods of drought of considerable length by 

 persistant cultivation to check evaporation. The soil, how- 

 ever, must have contained a good supply of moisture before 

 the beginning of the drought. The only reason corn can stand 

 dry weather better than the small grain crops is because cul- 

 tivation is possible during its growth, lessening the evapora- 

 tion from the soil. 



64. The Application of Manure. As corn is a gross- 

 feeding plant and is able to make good use of such sources 

 of plant food as manure, it is the general practice to apply 

 barnyard manure to the corn crop, usually before the land is 

 plowed. As the greater part of the available manure is pro- 

 duced during the winter, plowing is generally deferred until 

 spring, so that all the manui-e may be put on the land. Plow- 

 ing under coarse stable manure, whether on sod or stubble 

 land, is objectionable from the standpoint of moisture con- 

 trol and probably also in the matter of getting the best use 

 of the manure. The coarse manure lying between the sub- 

 soil and the furrow slice quite effectively separates these two 

 portions of the soil and retards the movement of moisture 

 between them. Much better results can be obtained if the 

 land thus manured is thoroughly disked and the manure 



