58 KNAPP METHOD OF GROWING COTTON 



different quantities and since the soils vary in 

 their supply, it is well for the farmer to know 

 what his soil and plants need before investing 

 his money in fertilizers. The practical way for 

 the farmer to determine these facts is to observe 

 the growth of the plants on his land. If the 

 plants grow rapidly and make an abundance of 

 leaf and stalk it is evidence of a good supply 

 of nitrogen. If there is not a proportionate 

 amount of fruit it is a sure indication that the 

 soil needs phosphoric acid. On the other hand, 

 if the plant does not have a good color and tends 

 to drop its fruit before it reaches a fair size it 

 indicates that the soil requires potash. 



Most of the soils in the South are deficient 

 in both nitrogen and phosphoric acid, and 

 some in potash, so when commercial fertilizers 

 are bought their value depends upon their 

 content of these substances. If the farmer has 

 saved all manures and has grown cowpeas or 

 other legumes abundantly, he will rarely have 

 to buy nitrogen. 



For rich soils, or soils where a heavy crop of 

 peas, beans, or clover was grown the previous 

 year, use one part of cotton seed meal and three 

 parts of acid phosphate for cotton. For me- 



