THE CLUB ROOT 



139 



a few roots becoming greatly swollen, as shown in Fig. 

 57, and the leaves, instead of having the dark green 

 color of healthy foliage, become pale green or yellowish. 



FIG. 57. CIAir, HOOT OF < AliBAUK. 



Such an injury, of course, prevents the proper develop- 

 ment of the plant, which becomes worthless. 



The injury to other crops than cabbage is often 

 severe. Cauliflower is frequently attacked with fatal, 

 effect, as may be seen in the photo-reproduction in Fig. 



