MIGNONETTE DISEASE 319 



Cercospora viticola, Sacc. Forms irregular, dry, brown 

 spots on vine leaves, and is most abundant during a damp 

 season. The discoloration extends through the leaf. Most 

 abundant on the lower, shaded leaves. 



Cercospora beticola, Sacc. Forms irregular, dry, pallid 

 blotches on leaves of beet (Beta vulgaris). Can be held 

 in check by spraying with Bordeaux mixture. 



MIGNONETTE DISEASE 



(Cercospora resedae, Fuckel) 



This fungus often proves destructive to cultivated 

 mignonette, especially when grown under glass, causing 

 dry brownish spots to appear on the leaves. It can be 

 controlled by spraying with Bordeaux mixture. 



Cercospora violae, Sacc. This species causes dry, pallid 

 spots to form on the leaves of Viola odorata, the sweet 

 violet, and often proves troublesome when the plants are 

 grown under glass. Spray with dilute Bordeaux mixture. 



FAIRY-RING OF CARNATIONS 



(Heterosporium echinulatum, Cke.) 

 This disease often proves destructive to cultivated 

 carnations and pinks, especially when the plants are ex- 

 posed to a chill, or when a moist, warm period in spring 

 is followed by a sudden lowering of temperature. 



The characteristic arrangement of the small black 

 clusters of the fruit of the fungus in irregular circles, 

 seated on pale spots on the leaf, resembling the 'fairy- 

 rings ' formed in pastures by Marasmius oreades, renders 

 the determination of this disease quite certain, even 

 without microscopic examination. 



