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 
intérested 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 
