CHAPTER II 



DESCRIPTION OF THE COTTON PLANT 



The cotton plant is indigenous to the tropical regions 

 of both hemispheres. In its native home it is a perennial. 

 The cotton of the southern United States, and of all im- 

 portant cotton-prrtducing countries, is an annual, being 

 kiUed by the low temperatures of winter. Under cultiva- 

 tion it is a much branched herbaceous shrub ranging in 

 height from two to six feet. Cotton is grown primarily 

 as a source of fiber. From the seed various by-products of 

 considerable value are obtained. 



6. The root-system. — When a cotton seed is placed 

 in a warm, moist soil, it absorbs water and swells. Sub- 

 sequently the sfeed coverings burst and the radicle, and 

 the plumule, a short iiine later, grow out and elongate 

 in opposite directions. The radicle grows to form the 

 root-system while the pltmiule develops into the aerial 

 portion. The cotton plant, while possessing a strong tap- 

 root, produces the greater portion of its feeding roots in 

 the upper two to six inches of soil. The copious branching 

 which the root system exhibits enables the cotton plant 

 to draw its food suppUes from a large area of soil. 



7. Types of roots. — Cotton roots may be classed as 

 primary roots, and secondary roots. The primary root is 

 commonly termed the tap-root. It is a continuation of 

 the above-ground stem and from it the secondary roots 

 branch. The depth to which the primary root grows is 

 determined largely by the drainage conditions and the 



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