Rose. 



359 



Mildew (Sphcerotheca pannosa, Lev.). Description. This 

 fungus attacks roses which are grown under glass and also 

 those out of doors. It checks the growth of the young shoots, 

 and causes the leaves to remain dwarfed and curled, the edges 



FIG. 86. Black spot of roses. 



being generally rolled downward. At the same time, a white 

 powdery growth entirely covers the affected areas, and the 

 plants soon become so weakened that they possess no practical 

 value. Fig. 87 represents a leaf partially affected. 



Treatment. The treatment of mildews affecting plants grown 

 under glass has already been discussed under GREENHOUSE 



