XIX 



FIBER CROPS 



COTTON 



Climate and Soils 



432. Distribution. Cotton production is limited practically 

 to the area south of the thirty-seventh parallel of latitude. 

 while the larger and most intensive production is located south 

 of the thirty-fifth parallel. In Asia the limit of cultivation ex- 

 tends somewhat farther north. The possible production of cot- 

 ton is almost unlimited, since the largest land surface of the 

 globe is between the thirty-seventh parallels of latitude north 

 and south, in all habitable sections of which cotton can be 

 more or less successfully grown. Within this area, however, its 

 economic production is limited by the amount and distribution 

 of sunshine and rainfall, as well as by temperature. It is now 

 grown chiefly between parallels 20 and 37 north latitude. 



433. Temperature. The cotton plant is extremely sensitive 

 to temperature conditions. The plant requires four or five 

 months of uniformly high temperature during which time it 

 makes its vegetative growth. A cold spell during this period is 

 liable to cause fruiting and is not desirable. After having 

 made its vegetative growth, two or three months of cooler 

 weather, with a greater range in daily temperature, are desirable 

 to bring about fruiting and ripening. 



For the best production of cotton there should not be killing 

 frosts later than April first nor earlier than November first, and 

 when fifteen days may be subtracted and added to these dates 

 the conditions are considered even more favorable. In the more 



340 



