Rose. 361 



Treatment. The treatment recommended against the rust 

 will also apply to this disease. In addition, however> the 

 affected steins 'should be removed as soon as discovered. 



Rust (Phragmidium mucronatum, Winter). Description. All 

 the young green parts of the rose are subject to the attacks of 



I 



FIG. 88. Rose Phragmidium. 



the rust fungus. It causes the formation, in early summer, of 

 small reddish-yellow spots which gradually increase in size as 

 the season advances. The stems frequently become bent and 

 twisted by the growth of the mycelium. During August, the 

 color of the spots changes to dark red. In the fall, small dar> 



