DISEASES OF THE APPLE. 243 



and twigs sending in little suckers (haustoria) which rob the 

 plant of food substance. 



Description: Dr. Bessey, in his paper "The Botany of the 

 Apple Tree" read before this society in 1894 says: 



"The leaves ofyoung trees, especially those in the nursery, are 

 quite subject to the attacks of a powdery mildew which covers 

 their surface with a white powdery coat. The leaves soon be- 

 come somewhat curled and wrinkled and eventually are greatly 

 injured." 



Hoiu spread: "The summer spores blow away in the wind, 

 and under favorable conditions germinate quickly and give rise 

 to a new growth of the fungus. Later in the season, usually 

 not until the autumn, the fungus produces its small spherical 

 fruits which are black in color and barely large enough to be 

 seen with the naked eye." 



These germinate the next spring and infect the young leaves 

 of the apple. 



Treatment: All the old leaves should be burned in the fall or 

 early spring. Spraying a few times in the spring will usually 

 check this disease. For this spray Dr. Bessey recommends a 

 solution of ammoniacal carbonate of copper, 



PINK ROT. 



Cause: The fungus which causes this disease is known as 

 Cephalothecium noseum. It was first described in 1836, but not in 

 connection with the apple 



Description: Pink rot is an attendant of apple scab and should 

 be looked for wherever scab is present. When it once gets a 

 start it is very destructive. The scab spots, or any injury, make 

 a good place for the entrance of the spores, where they germi- 

 nate and grow beneath the skin for a time. The skin is finally 

 ruptured and a white fungus, turning gradually to a pink color, 

 makes its appearance. The apple turns a brown and the spots 

 sink a little below the surface. The entire apple may become 

 affected. 



Hmo spread: The spores are carried by currents of air, by 

 insects, are washed by rains, or when the apples are in piles, 

 drop from apple to apple. 



