ete 1 
New YorkK AGRICULTURAL EXPERIMENT STATION. ~ 197 
We have seen no severe case of gumming except that caused 
by the fruit bark-beetle, Scolytus. In September, the gumming 
of peach trunks due to the attacks of Scolytus was very general 
in Niagara County. For an account of this see Bulletin 180 of 
this Station. 
Crown gall occurs frequently on nursery stock and occasionally 
on orchard trees. 
We have seen no powdery mildew, Spherotheca pannosa 
(Wallr.) Léy., the past season. 
PEAR DISEASES. 
Fire Buieut (Bacillus amylovorus (Burr.) De Toni.).—This dis- 
ease was common and did considerable damage, but not as much © 
as usual. . 
Lear Scorcu.—On August 12 we observed at Geneva a black- 
ening of pear leaves which resembled the work of fire blight, but 
was, in reality, due to leaf scorch. The trees on which it 
occurred were of the variety Kieffer, about ten years old, other- 
wise healthy and growing rapidly. Over a considerable portion 
of the tops of many trees the leaves were black and dead. For 
the most part, the injury was confined to about two or three feet 
of the terminal portion of vigorous shoots of the present season’s 
growth. Only the leaves were affected. The wood was unin- 
jured and this fact is proof that the trouble was not fire blight. 
In the course of abbdut two weeks most of the blackened leaves 
fell and the injury was then less conspicuous. 
We are convinced that it was weather injury similar to the leaf 
scorch which appeared on cherries in 1899; but we are at a loss 
to account for its occurrence this season when cherries have been 
free from the trouble; whereas, in 1899, cherries suffered from 
leaf scorch when pears were exempt from it. We know posi- 
tively that the Kieffer orchard affected with leaf scorch in 1900 
was wholly free from it in 1899. Even pear trees mingled with 
the badly scorched cherry trees in the Maxwell orchard in 1899 
showed no signs of leaf scorch.*! 
See Bul. 162 of this Station, p. 173. 
