GRASSES OF IOWA. ' 275 



Quite a number of farmers of Grundy county in the early 

 days planted hedges of buckthorn around their farms. Mr. 

 Stout had observed for a number of years that oats are very 

 badly rusted in the vicinity of these hedges, so that he had 

 learned not to plant any oats in the immediate neighborhood. 

 Away from these hedges rust was not so severe. For the 

 farmers of the vicinity the buckthorn hedge and rust was an 

 instructive and valuable lesson. 



SIMPLE BARLEY RUST. 



Puccinia simplex. — In 1865 Koernicke described, under the 

 name of Puccinia straminis var. sim%)lex, the rust upon barley. 

 This rust appears to be quite common in Scandinavia, Belgium, 

 Hungary and Austria, ^cidium unknown. The uredo spores 

 occur in small sori which are longer than wide. These occur 

 scatteringly upDn the upper surface of the leaf. The lemon- 

 colored spores round or short elliptical, spiny, yellow, 19 to2C" 

 in diameter or 22-27" x 15-19". 



RUSTS OF OTHER GRASSES. 



It will not be necessary to discuss at any length all of the 

 rusts which are common on grasess and cereals, since they 

 have in part been treated ia a former discussion; suffice it 

 to say that a so-called Puccinia grominis occurs on blue 

 grass, but it is not common nor destructive in this state. 

 The same species occurs on orchard grass. Puccinia graminis 

 is, however, extremely common on bent grass (Agrostis alba) 

 and several of the related species. Puccinia graminis, or a 

 closely related species, the Puccinia agropyri, is very common 

 on the following species of the genus: Agropyron repens, A. spi- 

 catum, A. caninum and A. tenerum. Until it has been deter- 

 mined whether this form is distinct in America, it will be better to 

 treat it with common grass rust, which it resembles in a great 

 many respects, and Carletou has shown by inoculation experi- 

 ments that P. graminis occurs on several species of Agropyron. 



Pucinnia coronata. — So far as the writer knows, this species 

 is common only upon the orchard grass in the state of Iowa, 

 and this is the form which has been referred to P. coronata dac- 

 tylidis. In Europe, however, this rust is common on other 

 grasses. 



Timothy rust {Puccinia jMei pratensis). — Timothy, so far as 

 the writer knows, is not affected with any rust in the state of 



