540 



VARIOUS FERTILITY FACTORS 



gen, 4 pounds of phosphorus, and 2 of potassium may be dropped 

 in or near the hill of corn with a " fertilizer attachment " to the 

 planter, and, under adverse conditions of soil and season, the crop 

 increase may show some profit. It should be clearly understood, 

 however, that all such systems of fertilizing are of themselves 

 only an aid to soil depletion, because the " good start " thus given 

 to the crop enables it to draw upon the soil itself for larger supplies 

 of one or more elements of plant food than would be furnished 

 by the untreated soil and the fertilizer applied. 



Quite independent of any such practices, the landowner should 

 make ample provision for maintaining the fertility of the soil, 

 on normal soil, by large use of phosphorus and farm manure or 

 legume crops and crop residues, sufficient limestone being applied 

 when necessary to prevent or correct soil acidity. Where this is 

 done, however, the use of " starters " is usually unnecessary and 

 unprofitable. Indeed, the dropping of a small quantity of fertilizer 

 in the hill of corn (or near it) is sometimes a source of damage, 

 not so much because it may injure the seed or young plant, but 

 because it does not encourage the normal development of the root 

 system in proportion to the early growth of the plant, and as a 

 consequence the crop may suffer from drouth later in the season 

 much more than the unfertilized corn. 



