FUNGI AND FUNGICIDES. 7 



POWDERY MILDEW OF APPLE, PEACH, AND OTHER TREES. 



During the summer months one may notice the leaves and 

 new growth of fruit trees covered with a thick, white, felt-like 

 covering. These are the mycelium of the powdery mildew 

 fungus. This fungus belongs to the external group, the 

 mycelium of which live on the outside of the plant and do not 

 enter the tissue of the leaf. Early in the fall of the year the 

 winter spores are developed and consist of very minute, round, 

 black masses, which remain on the fallen leaves or twigs dur- 

 ing the winter and from which start the next season's brood. 



Use the ammoniacal solution of copper carbonate when the 

 leaves first open, and in very bad cases repeat three or four 

 times at intervals of fourteen days. 



BITTER ROT OF THE APPLE. 



This fungus has appeared in various apple districts. The 

 time to spray for it is when it first makes its appearance. 

 This disease can be easily recognized by the presence of small 

 blackish pustules scattered over the surface of the apple. 

 These are the fruiting spots of the fungus. The mycelium 

 enter the pulpy tissue of the fruit and cause the rot to appear 

 in little brown specks underneath the skin. 



In very bad cases the first spraying should be followed by a 

 second and third spraying at intervals of two weeks, using the 

 ammoniacal copper carbonate solution. 



PRUNE-LEAF RUST. 



The leaves of the prune and other stone fruits are often 

 attacked by reddish spots on the surface and yellowish-brown 

 spots on the under side. Sometimes this attack is so severe 

 as to cause the dropping of the foliage. 



Spraying with the Bordeaux mixture (diluted formula) just 

 after the buds start, and continued at intervals of ten or 

 fourteen days during the growing season, will do much toward 

 checking the fungus. 



PEAR BLIGHT. 



This disease, while not belonging to the group of fungous 

 diseases on which we are treating, has become so important in 

 this State and is doing such destructive work that allusion to 



