New York AGRICULTURAL ExpERIMENT STATION. 195 
berries of the variety Wilson Jr., the rust-affected canes were 
almost or even wholly destitute of prickles. It is not an uncom- 
mon thing to find healthy canes and rusted canes of blackberry in 
the same hill.** Such cases offered an opportunity for close com- 
parison and it was found that the difference in the number of 
prickles on the two sorts of canes in the same hill was very marked. 
(See Plate XV.) The difference is so great that Mr. E. W. Barns 
says he can pick out the diseased canes in winter by their freedom 
from prickles. On affected raspberry canes the reduction of 
prickles was very evident but not so marked as with the black- 
berry. | 
After these observations at Middle Hope, we examined, during 
the season, many rusty blackberries, raspberries and wild dew- 
berries (ubus canadensis L.) in various localities. With all of 
these plants we found that rust in some cases caused a great re- 
duction of prickles; in other cases, partial reduction; and in still 
others, no reduction at all. At Yorktown badly rusted blackberries 
of the variety Minnewaska were observed which showed no ap- 
parent reduction of prickles. 
LEAF SPOT. 
(Septoria rubi Westd. ) 
Rare. Observed only at Poughkeepsie. 
CHERRY DISEASES. 
FRUIT ROT. 
(Momlia fructigena P.) 
As usual, fruit rot has been the worst cherry disease, but was not. 
nearly so destructive as in 1898. From Westchester Co. it is 
reported ‘“‘ bad on some varieties.” In Rockland Co. it destroyed 
13 This has also been observed by Clinton; Orange Rust of Raspberry and 
Blackberry. Il]. Agr. Exp. Sta. Bul. 29: 276. D. 1893. It occurs less com- 
monly with the raspberry, probably on account of the more compact habit ef 
growth at the crown. 
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