342 THE FORAGE AND FIBER CROPS IN AMERICA 



northerly sections of the cotton belt killing frosts occur as late 

 as April 15 and as early as October 15, which is about the limit 

 of successful cotton culture. 



434. Rainfall. While the cotton plant is extremely sensitive 

 to temperature conditions, this alone is not sufficient for its eco- 

 nomic production. During the growing period of the cotton 

 plant the rainfall should be abundant and well distributed, while 

 during the ripening period comparatively dry weather is desir- 

 able. Wet weather during picking is very injurious, especially 

 when accompanied by high w r ind. Suitable conditions of rainfall 

 and sunshine are more likely to occur inland than upon the coast. 

 Upland cotton is therefore grown inland, while sugar cane 

 and rice are more likely to be grown near the coast in tropical 

 and semi-tropical countries. 



435. Soils. While under proper climatic conditions cotton 

 can be raised upon all ordinary soils with a fair degree of suc- 

 cess, the plant is greatly modified by the character of the soil 

 upon which it is grown and upon the same soil by the amount of 

 rainfall. As a rule sandy soils produce the smallest yields, but 

 these can be depended upon for a crop under rather wide cli- 

 matic conditions. Under the proper climatic conditions clay 

 soils and silty clays produce the maximum crops, although 

 under excessive rainfall the plant may run to wood, or as the 

 planters say, to weed, with small production of lint. Uplands 

 produce comparatively small plants which mature early, while 

 bottom lands and rich black prairies produce much larger 

 plants which mature later. 



Cotton grown on some soils is more subject to disease and in- 

 sect enemies than when grown on other soil types. As for most 

 other crops, especially those which receive intercultural tillage, 

 loam soils are considered safest, and are for other reasons pre- 

 ferred. Mellow, friable soils are more easily worked by light 

 machinery. From a study of the different types of soils it is 



