New Yorx AqricutturaL Experiment Station. 461 
preventive treatment which can be recommended is digging out 
and burning the infested plants immediately upon the first ap- 
pearance of the disease. This treatment will materially check 
the disease. Affected plants may usually be detected before the 
rust breaks out on the leaves. The diseased leaves have a pale 
orange tinge and present a sickly appearance which one soon 
comes to recognize as characteristic of rust-infested plants. Di- 
seased canes are also apt to be much freer from .prickles than 
are healthy canes. 
LEAF-SPOT. 
(Septoria rubt Westd.) 
A leaf-spot of raspberries is caused by the same Septoria which 
attacks blackberries. It is discussed on page 419. 
The disease seems to be less troublesome on raspberries than 
it is on blackberries. 
ROOT KNOT. 
The roots of raspberries are often covered with galls which 
are similar to those found on peach roots (see page 437) and are 
_ probably due to the same cause. Our knowledge of these root 
galls is imperfect. To both raspberry and the peach they are 
very injurious. There is some reason for believing that the di- 
sease may be communicated from the peach to the raspberry and 
vice versa. Hence it is advisable to avoid planting peaches on — 
soil in which raspberries have knotted badly. Neither should 
raspberries be planted where peaches have been affected with the 
root knot. 
RASPBERRY INSECTS. 
CANE MAGGOT. 
(Phorbia sp.) 
Description.— This insect works only in the new shoots causing 
them to wilt and finally die. This wilting of the shoots is first 
noticeable in May. ‘The adults first appear in spring toward the 
