THE BOTANY OF THE APPLE TREE. 



35 



early spring before the opening of the buds with a solution of lye,* 

 which he says he "has clearly demonstrated very materially checks 

 the outbreak of scab." 



FIG. 7. Apple scab. A, a mag- 

 nified view of a cl uster of small 

 specks; B, portion of the fun- 

 gus highly magnified; C, part 

 of B magnified still more. 



FIG. 8. Apple scab. A, an apple 

 with well developed scab; B, 

 section through a scab highly 

 magnified, showing a few de- 

 tached spores at S. 



Bitter-rot or Ripe-rot. This troublesome disease appears upon the 

 surface of the mature apple in the form of brownish or blackish spots 

 which are at length studded with minute black points (Fig. 9). 

 These diseased spots extend deep into the fruit, and are noted for hav- 

 ing a peculiarly bitter taste. The fungus which produces bitter-rot 

 is also one of the so-called "Imperfect Fungi," and is known as 

 Gloeosporium frutigenum. 



*The solution used by Professor Alwood is made as follows: 



Concentrated lye 8 cans. 



Water 50 gallons. 



| In Bulletin 17 of Virginia Agricultural Experiment Station, p. 64. 



