COLE CROP PROJECTS 



107 



rot. Cabbage seed should be soaked from ten to twenty min- 

 utes in formaldehyde (one teaspoonful to a pint of water). 



Club root attacks the roots and stems, causing them to become 

 swollen and enlarged. Often infected plants remain stunted 

 and do not produce 

 heads. The organ- 

 ism causing club 

 root lives in the soil 

 and is spread by 

 wind, in manure, on 

 seedling plants, 

 weeds, and tillage 

 tools. Club root may • 

 be controlled by lim- 

 ing the soil. Slaked 

 lime should be ap- 

 plied in the fall at the 

 rate of about seventy- 

 five bushels- per acre and should be well worked into the soil. 

 Crop rotation should be practiced, allowing cabbage to be groTUTi 

 on the same soil only once in about five years. Varieties Hol- 

 lander, Stone, Mason, and Henderson's Early Summer are some- 

 what resistant. 



Yellows or wilt is a disease characterized by yellowing and 

 dropping of the leaves. Plants often die. Control is similar to 

 that described for black rot. The variety Wisconsin Hollander 

 is resistant. 



Other diseases of cabbage of less importance are black leg, 

 downy mildew, and soft rot. 



1. What ^e the symptoms of black rot of cabbage? 

 SH : 165-166. 



Fig. 32. - 



-Club root is the most serious disease of 

 cabbage and related crops. 



