Mereanre: Tur Cuesrnur Bark Dristasr 11 
SECOND STAGE OF THE DISEASE. 
One after another, the limbs are invaded by the parasitic spores, and quickly succumb. A 
peculiar ragged appearance in the tree is produced, due to the fact that many branches 
have not yet been girdled by the fungus, and therefore retain their normal foliage. 
When 
the canker begins in the trunk, it rapidly extends until it girdles the whole tree, and death 
guickly results. (Pigure 3.) 
in the form of long, irregularly twisted 
strings or horns (fig. 6), which are at 
first bright yellow to greenish yellow, or 
even buff, becoming darker with age. 
If the canker is on the trunk or a large 
limb with very thick bark there is no 
obvious change in the external ap- 
pearance of the bark itself, but the 
pustules show in the cracks (fig. 7), and 
the bark often sounds hollow when 
tapped. After the limbs or trunks are 
girdled the fungus continues to grow 
extensively through the dead bark, 
sometimes, if conditions of moisture are 
favorable, covering the entire surface 
with the reddish brown pustules (fig. 7). 
These pustules produce mostly the type 
of spores called ascospores. If the 
proper conditions of moisture are present 
the fungus may grow on the bark of 
chestnut logs and even upon bare wood. 
When a branch or trunk ts girdled the 
leaves beyond change color and sooner 
or later wither (figs. 2, 3, 4, and 8). 
These prematurely killed leaves often 
remain on the branches, forming, to- 
gether with the persistent burs, the 
most conspicuous winter symptom of the 
disease (fig. 8). Suspicion has been 
recently aroused in some quarters that 
the dwarfed and abortive nuts in these 
burs may under some circumstances be 
unwholesome, or even poisonous, when 
eaten. So far, however, the evidence 
on this point is wholly inconclusive. 
CONSPICUOUS SYMPTOMS. 
The most conspicuous symptom at 
all times of the year is the occurrence of 
sprouts at the base of the tree, on the 
