﻿THE PATHOLOGY OF ORNAMENTAL PLANTS 

 Mel. T. Cook 



The rapid development of plant pathology in America has 

 resulted in giving a far better understanding of the diseases of 

 certain groups of plants than of others. While we find a rather 

 extensive literature on diseases of field crops, fruits, and 

 vegetables, we find a very meager literature on the diseases 

 of ornamental plants. 



In that period which preceded the rise of plant pathology the 

 mycologists devoted their attention primarily to the study of the 

 taxonomy, morphology, and life history of the parasite, and it must 

 be admitted that the work of these men was superior in many ways 

 to much of that which has come from the more recent students in 

 the new school of plant pathology. 



The treatment of plant diseases was the first real step in plant 

 pathology following the work in taxonomic mycology, but with the 

 advance of the subject it soon became evident that the plant 

 pathologist should give a great deal of attention to the symptoms 

 and progress of the diseases. This involves a knowledge of the 

 physiology of both the host and the parasite, and also a knowledge of 

 the chemistry of the plant and of the fungicides to be used. 



The efforts of the plant pathologists were very naturally directed 

 to those crops which produced food and clothing, and more espe- 

 cially to those crops which required a maximum amount of personal 

 attention on the part of the grower. Consequently, we find a 

 rapid advancement of the science in the studies of the diseases of 

 fruits and vegetables, closely followed by studies on field crops, 

 forest trees, and shade trees. 



The apparent neglect of the diseases of ornamental plants is 

 due to three causes: (i) most people do not look upon ornamental 

 plants as being of economic importance; (2) many of the growers 

 of ornamental plants have received little or no satisfaction from 

 the plant pathologist and have therefore developed many methods 

 which they frequently hesitate to make public; (3) the plant 

 67] [Botanical Gazette, vol. 61 



