THE PRINCIPAL DISEASES 



OF 



CITRUS FRUITS IN FLORIDA. 



(By Walter T. Swingle and Herbert J. Webber.) 



REPRINTED FROM BULLETIN NO. 8, OF U.S. DEPARTMENT 



OF AGRICULTURE DIVISION OF VEGETABLE, 



PHYSIOLOGY, AND PATHOLOGY. 



INTRODUCTION. 



IT is the purpose of this bulletin, to give in as brief and 

 concise a manner as possible, an account of some of the 

 principal diseases of citrus fruits, especially those occurring in 

 Florida. The following are the diseases which we will 

 endeavour to describe : — Blight, die-back or axanthema, scab or 

 verrucosis, sooty mould, foot rot or mal-di-gomma, and 

 melanose. 



The diseases of citrus fruits have received more or less 

 attention from the Department, through the division of 

 Vegetable Physiology and Pathology, since the year 1886. In 

 1891, Professor L. M. Underwood was sent to Florida to make 

 a preliminary study of this subject. Later the same year one 

 of the writers, with Tr. Erwin F. Smith, was sent to Florida 

 to carry on further stuc ies, especially on blight, and the follow- 

 ing spring the former returned to continue the work. In the 

 fall of 1892 a slightly increased appropriation enabled the 

 Department to station both writers regularly in Florida. A 

 laboratory especially erected for the purpose was donated hy 

 the citizens of Eustis, Fla., and this point was made our head- 

 quarters. Since the completion of the building both laboratory 



