FORAGE CROPS 



395 



The disease is very widespread, but even in the worst 

 seasons does not do much 

 injury. 



Angular leaf spot (Cer- 

 cospora cruenta Sacc). — 

 The angular leaf spots of 

 this disease are a famil- 

 iar sight in most cowpea 

 fields. They are of vari- 

 ous colors above, chiefly 

 reddish, and are gray to 

 purphsh or slate-colored 

 below. 



The damage is rarely 

 very great. In some in- 

 stances the attack may 

 proceed to the stems, 

 where, especially at the 

 base, it may cause crack- 

 ing and result in such 

 lowering of the vigor of 

 the plant as to cause 

 shedding of leaves and 



failure to properly fill the pods. The loss of leaves is of 

 course serious to the hay value of the crop. 



Fig. 172. — Leaflet of cowpea showing cer- 

 coaporose spots. Original. 



JAPAN CLOVER 



Powdery mildew {Microsphoei-a diffusa C. & Peck). — 

 The usual characters of the powdery mildews distinguish 

 this disease sufficiently. The injury to this valuable 

 southern forage plant, while considerable, is never suffi- 

 cient to call for treatment. 



