FORAGE CROPS 397 



Smut (Ustilago striwformis (Westend.) Niessl.). — This 

 is the smut described under timothy. It has been known 

 to affect 30 per cent of the plants, and to reduce the seed 

 yield from 300 hundredweight to 70 hundredweight. 



Anthracnose. See rye. 



TALL OAT GRASS 



Smut {Ustilago perennans Rostr.). — This smut closely 

 resembles that of oats, though the flower parts are not 

 so completely destroyed as is the case in oat smut. The 

 disease is perennial in its perennial host, and smutted plants 

 bear smut, year after year. 



TIMOTHY 



Smut {Ustilago striceformis (Westend.) Niessl.). — This 

 smut occurs chiefly upon the leaves, more rarely upon 

 other parts of timothy, as well as upon some species of 

 Agrostis, Poa, and Elymus. The spore masses form long 

 black lines upon the leaf, and by merging and rupturing 

 reduce the leaf to a torn, blackened state. The affected 

 plants are weakened, small, and often fail to make seed. 

 The disease perenniates with the host. Infection proba- 

 bly occurs through the seed. 



Rust {Puccinia graminis Pers.). — This rust in general 

 resembles the black rust of the grains. It was first 

 reported in 1882 and has of recent years increased rapidly. 

 It does not seem to be communicable to other grasses. 



Anthracnose. See rye. 



VETCH 



Spot (Protocoronospora nigricans Atk. & Edg.). — Upon 

 the stems, leaves, and bracts of vetch very characteristic, 



