Introduction 



a. Only young heart leaves wilted. Wilting usually most appar- 



ent at tip of leaves. Later these tips become dry and brown. 

 Look for Tarnished Plant-bugs (pages 

 122-123). 



b. Entire plant more or less wilted. 



* Root either covered with whitish substance or with abnor- 

 mal development of fine roots or wart-like swellings. 



Root more or less covered with a white mould-like 

 substance. Many whitish-yellow lice mixed with 

 this substance. Lice present in nearly every 

 field regardless of previous crop. Damage more 

 apt to be severe in dry years than wet. 



Sugar Beet Root-lice (pages 55-59). 



00 Root with abnormal development of fine rootlets. 

 Many small pearly-white bodies clinging to these 

 rootlets. (See Figure 9, Plate III, Page 15 and 

 Figure 6, Page 60). In late fall many of these 

 bodies become rich brown in color. Injury most 

 apt to occur on old beet ground. 



Sugar Beet Nematode (pages 59-64). 



000 Roots with wart-like swellings. Rootlets with 

 small, almost round swellings resembling beads on 

 a string. (See Figure 8, Page 64). Injury most 

 apt to occur on old beet ground. 



Root-knot Nematode or Gallworm 

 (pages 64-66). 



** Root normal. Not as above. 



Damage usually most severe in fields near poor 

 stands of alfalfa overrun by shepherd 's-purse, 

 fanweed and other weeds of the mustard family. 

 Fields adjacent to waste land overgrown with 

 these weeds very apt to be damaged, also, as weeds 

 begin to ripen. 



Look for False Chinch Bugs (pages 1 19- 



B. Leaves dull green, light yellow, or blotched with whitish green 

 or purple. 



1. Leaves dull green, as though plants were suffering from lack of 

 moisture. In severe cases leaves become light yellowish green. 

 Plants making poor growth. 



Look for : Sugar Beet Root-lice (pages 



55-59); 

 Nematodes (pages 59-66). 



