33^ 



BOTANY OF CROP PLANTS 



The principal varieties grown in the United States may 

 also be classified as follows (in each division but one or two 

 examples are given) : 



Flesh white. 



Root entirely white. 



Flat (Early White Flat Dutch Strap-leaved, Extra Early White Milan). 

 Spherical (Snowball, White Globe Strap-leaved). 

 Oval (White Egg). 

 Carrot-shaped (Cow-horn). 



Fig. 140. — Types of turnips (Brassica rapa). A, flat; B, tankard or spindle; 

 C, globe; D, long. (After Percival.) 



Root purple or red at top, white below. 



Flat (Purple Top Strap-leaved, Extra Early Purple-topped MUan). 



Spherical (Purple Top White Globe). 

 Root entirely red (Scarlet Kashmyr). 

 Flesh yellow. 

 Root entirely yeUow (Golden Ball). 

 Root green at top, yellow below (Amber Globe), 

 Root red at top, yellow below (Early Red Top Globe). 



Structure and Uses. — It will be recalled that the greater 

 portion of a turnip is tap root. In cross-section, it shows the 

 following layers (Fig. 141) : 



1. Outer layer or cortex (bark). 



2. Cambium. 



3. Main flesh of turnip (wood and pith). J 



