2 
NEIL E. STEVENS 
Opportunity for comparison. Consequently in this work special care 
was taken to have inoculations made in the same way and on trees 
as nearly similar as possible but in different localities. It was desired 
of course to make observations at stations climatologically as different 
as possible. The actual location of inoculations was however governed 
by practical considerations. In order to avoid spreading the chestnut 
blight beyond its present range it was necessary to confine work to 
regions where the disease was so well established as to leave no hope 
of eradication. A quantity of healthy chestnut was obviously neces- 
sary. The latter consideration excluded the entire region between 
Philadelphia and New Haven, Connecticut. With the exception of 
one locality (Overlook Mountain) the inoculations were all made near 
regular U. S. Weather Bureau observation stations.^ 
The stations selected were Concord, N. H.; Williamstown and 
Amherst, Mass.; Hartford, Conn.; Wilmington, Del.; Van Bibber, 
Woodstock, and Frederick, Md.; Washington, D. C; and Fairfax and 
Charlottesville, Va. The distance from Concord to Charlottesville is 
about 500 miles, or about 5 degrees of latitude. In addition to regular 
inoculations at these stations inoculations were made at various 
elevations on Overlook Mountain in the Catskills in order to determine 
whether difference in altitude would make any perceptible difference 
in the growth and fructification of Endothia parasitica. Overlook 
Mountain was selected as being the only place known to the writer 
where chestnut grows through a considerable range of elevation and 
where the chestnut blight is present. Graylock Mountain near 
Williamstown, Mass., was first selected but chestnut was not found on 
this mountain above 1,500 feet. 
Work was begun in the spring of 191 4 and each station visited once 
in five or six weeks during the summer of 1914 and twice during the 
summer of 1 91 5. At each visit ten or more inoculations were made on 
healthy chestnut trees and the condition of previous inoculations 
noted. The trees inoculated were uniformly second growth and as 
far as possible were from 6 to 8 inches in diameter. Wherever these 
conditions were not met the fact is indicated in the report of obser- 
vations. The inoculations were made by cutting through the bark 
with a sharp knife and inserting a quantity of mycelium and spores 
from a pure culture, usually on corn meal, with a freshly cut twig. 
^ In the selection of these stations, as well as in the interpretation of weather 
data, the writer had the advice of Mr. L. M. Tarr, local forecaster, U. S. Weather 
Bureau, New Haven, Conn. 
