22 CHESTNUT TREE BLIGHT. 
branch may or may not attain full size, according to whether the 
girdling by the disease was completed late or early in the spring. 
These burs-commonly persist on the tree during the following win- 
ter, thus producing the only symptom which is at all conspicuous 
during the leafless season. The great damage which the disease has 
done in the late summer thus becomes most evident at the beginning 
of the next season, and that done in the spring becomes evident later 
in the same season, giving rise to the false but common idea that 
the fungus does its work at the time of year that the leaves change 
color, when in reality the harm was done much earlier. 
Fic, 4.—Dead chestnut bark showing pustules of the parasitic fungus bearing winter spores. 
Perhaps the most easily seen as well as the longest persistent 
symptom of the bark disease is the prompt development of sprouts, 
or “suckers,” on the trunk of the tree (fig. 3) and at its base, or 
somewhat less frequently on the smaller branches. Sprouts may 
appear below every girdling lesion on a tree, and there are usually 
pee such lesions. These sprouts are usually very luxuriant and 
quick growing, but rarely survive the second or third year, as they 
in turn are killed by the fungus. The age of the oldest living sprout, 
as determined by the number of its annual rings, is an indication of 
the minimum age of that portion of the infection immediately above 
