TREATMENT OF DISEASES INJURIOUS TO ORCHARD CROPS. 79 



fungus as that which causes the black rot of Apple fruit. The body blight 

 of Pears is also shown to be due to the attacks of one or, possibly, 

 more fungi. This is quite distinct from the fire blight, which is a 

 bacterial disease. Progress is also being made in the study of root rot in 

 certain orchard trees, and of the crown gall found in orchard and nursery. 

 Experiments in the treatment of some of these troubles are under way. 



The limitations of this discussion of recent developments in the treat- 

 ment of diseases and insects injurious to orchard crops have prevented 

 any detailed consideration of the topics which have been touched upon. 

 Many things which seem to be of minor interest have necessarily passed 

 unnoticed. The purpose of the ^mter has been to give a brief resume of 

 the development of modern orchard operations against insects and plant 

 diseases, and set forth their present status in the orchard sections of the 

 Eastern United States. It seems appropriate at the close of one century 

 and the opening of another to set a stake to mark the present achieve- 

 ments in this line of horticultural progress. 



Fig. 14. — Cory\nthes Mastebsiana. {Gardeners' Chronicle.) 



