314 The Spraying of Plants. 



MIGNONETTE. 

 FUNGOUS DISEASES. 



Leaf Blight; Mignonette Disease (Cercospora Resedce, 

 Feckl.). Description. "The disease first appears either as 

 minute pale spots with brownish or yellowish borders, 

 little sunken areas in the succulent tissue of the leaf, or 

 as reddish discolorations which spread over the leaf and 

 finally develop into these pale spots or patches. The spots 

 when young are simply dead portions, uniformly brown 

 throughout ; but as they become older and larger, little black 

 specks appear in their centers, giving a somewhat granular 

 cast. The disease spreads very rapidly over the leaves, the 

 dead areas grow larger and more irregular in shape, the 

 leaves commence to curl, wither, and hang limply against 

 the stems." 1 



Treatment. Early and repeated sprayings of the young 

 plants with the Bordeaux mixture or ammoniacal carbonate of 

 copper will almost entirely prevent the disease. 



MOSSES AND LICHENS. 



It is very rare that these growths injure the cultivated plants 

 upon which they are found. But they often lend an unkempt 

 air to a plantation, and for this reason, if for no other, their 

 removal appears desirable. Bordeaux mixture has frequently 

 cleaned fruit trees of these plants, and its general use for this 

 purpose may be recommended. Alkaline washes have a similar 

 action. Spanish moss, which in the Southern States appears to 

 have an injurious action upon certain trees, may be destroyed 

 by spraying the tree with a wash composed of eight cans of con- 

 centrated lye dissolved in fifty gallons of water. It is possi- 

 ble that strong fungicides would exert a similar influence. 



MUSKMELON. 

 FUNGOUS DISEASES. 



Powdery Mildew ; Cucumber Mildew (Plasmopara Cubensis, B. 

 & C.). Description. This disease has been reported as having 



i Fairchild, Ann. Repl. U. S. Com. of Agric. 1889, 429. 



