CEREALS 



359 



Fields should be examined for the presence 

 of ergot. If large quantities be found, the 

 grass should not be used for hay or pasture. 

 Ergot can be lessened by cutting susceptible 

 grasses about flowering time, thus checking 

 the spread of the fungus. Badly infected hay 

 lands should be burned over to destroy scle- 

 rotia; roadside grasses should be cut often 

 enough to prevent the formation of ergot, 

 and seed should be examined to prevent the 

 spread of ergot through this means. 



Black stem rust {Puccinia graminis Pers.). 

 — This rust is perhaps identical with the black 

 stem rust of wheat, and the description given 

 in that connection applies here. 



Orange leaf rust (Puccinia rubego-vera 

 (DC.) Wint.). — This rust bears a very close 

 resemblance to the rust of similar name upon 

 wheat, but in careful inoculation experiments 

 it has been impossible to infect one of these 

 hosts from the other. It is invariably present 

 where rye is grown and is particularly abun- 

 dant in the Southern States, though not- 

 withstanding its universal presence it is not 

 destructive. The uredo mycelium remains 

 alive and continues to produce spores over 

 winter in the leaf in the South, as it probably 

 does in colder climates as well. It is possible 

 that it is in this way carried from season to 

 season by volunteer rye in the fields. The 

 cluster-cup stage occurs upon a member of 



Fig. 154. — 

 Leaf of rye 

 showing or- 

 ange leaf 

 rust. Orig- 



[ inal. 



