Ornamental Plants 439 



of dead tissue which often involve the roots for considerable 

 distances. The disease is the same as that of tobacco. Root- 

 rot (Corticium), see p. 21. 



Mold (Zygodesmus albidus E. & H.). — This mold forms a 

 white, fiour-like coat over the leaf. 



VIRGINIA CREEPER (Ampelopsis) 



Leaf-spot {Guignardia hidwellii, Phyllosticta) . — The spots 

 occurring upon the leaves and shoots are identical in ap- 

 pearance with those upon the grape, and the same treatment 

 is recommended. 



Powdery-mildew. See grape. 



Stem-rot {Cladosporium herbarum Lk.). — Large blanches 

 or even the entire plant may be killed. 



WATER-LILY 



Leaf-spot (Cercospora). — Circular spots, at first pale 

 green, later yellow, and finally Ijrown and dead, are produced 

 upon the leaves. The dead tissue may break away, leaving 

 irregular holes. 



Soda-Bordeaux mixture is recommended, since it is effec- 

 tive and does not spot the leaves. It is beneficial also in 

 removing undesired algal growth. Another leaf-spot is due 

 to Helicosporium nymphcearum Rand. — Dark spots often 

 red-bordered occur on the leaves and may enlarge to involve 

 the whole leaf. 



