CHESTNUT BARK DISEASE. 361 



Early Investigations. We are indebted largely to Murrill 

 (45-51) for our knowledge of the life history of the chestnut 

 blight fungus. He not only gave a careful scientific descrip- 

 tion of its different spore stages, but by inoculation experiments 

 proved that it could produce the disease in healthy seedlings. 

 He also tried various methods of control. 



The United States Department of Agriculture soon became 

 interested in the disease, and through the efforts of Metcalf 

 (33-39) and later of Collins (13-16) and others, facts concern- 

 ing the distribution, hosts, and control of the fungus were made 

 known. Metcalf (33) was the first to note the relative 

 immunity of the Japanese varieties to the disease, and to sug- 

 gest that the fungus was originally brought into this country 

 from Japan. He is also, more than anyone else, to be credited 

 for what good, if any, may arise from the attempted control 

 of the fungus by the cutting-out quarantine method, since it is 

 through his advocacy that this method has been undertaken in 

 Pennsylvania and perhaps elsewhere. 



The writer apparently was the next after Murrill and Metcalf 

 to take up the special study of the disease. He was the first 

 to try to prove that weather had some connection with the 

 trouble, and through his investigations, in connection with 

 Farlow, to show the relationship of the fungus to two other 

 species found in this country, all of which are now considered 

 species of the genus Endothia. 



Recent Investigations. With the spread of the blight to new 

 localities, and the appropriation of large sums of money by the 

 National Government and the State of Pennsylvania for its 

 special study and control, popular and scientific interest in this 

 disease was greatly augmented. The more recent investigations 

 have had to do largely with the detailed study of field conditions 

 in the different states, especially in the State of Pennsylvania, 

 where the force of scientific and general workers is larger than 

 on any other special botanical investigation ever carried on in 

 this country. This control work has been largely devised by 

 Foresters Williams and Detwiler (19, p. 129), based on the 

 cutting-out experiments of Metcalf at Washington (38). 

 Recently Carleton, of the United States Department of 

 Agriculture, has been given general control of all the work in 



