DISEASES OF CULTIVATED PLANTS 437 
Rust (Gymnosporangium sp.) also occurs upon the quince when trees are 
near cedars which carry the cedar apples and distribute spores. Labor must 
be devoted to the destruction of the source of infection as in the apple. 
RADISH 
Blacx-Rot, Club-Root. Black-rot (Bacterium campestre (Pamm) and club- 
root (Plasmodiophora brassicae Wor.) occur upon the radish at times and are of 
the same nature and cause as these diseases upon other mustards, especially 
cabbage and caulifiower. The attention to control will be similar to that for 
cabbage. 
Downy Mildew and White Mold (Peronospora parasitica De Bys and Cystopus 
candidus Pers.) also occur upon the leaves of radish, the latter more especially 
upon younger plants. These are the same diseases that have been described 
upon other mustard growths. 
RAPE 
Black-Rot, Club-Root, etc. Rape, as other mustards, is attacked by a group 
of diseases which are common upon plants of the mustard family. These are 
black-rot, club root, white mold, etc., that are more fully described under 
cabbage, cauliflower and radish. 
RASPBERRY 
Anthracnose (Codletotrichum venetum (Speg.) Hals.). The anthracnose 
ungus is a frequent bane to the raspberry grower. It attacks the young canes 
and so spots and injures them, as well as the foliage, that when the time arrives 
for ripening the fruit the plants are unable to do this and the crop is largely 
lost. The Horticulturist of this Station has always succeeded in holding this 
disease in check by use of the methods of spraying recommended in the cal- 
endar for anthracnose. Care, however, 
must be used in the application of the 
spray to reach the stems of the young 
canes and to keep the fungicide from 
do injury. : 
Cane Blight. Serious dying of 
raspberry canes has occured in some 
of the northern districts where they are 
largely grown. These troubles range 
from ‘‘dieback’’ to impaired vigor in 
which there are seeming brown patches 
upon the stems. As a rule these have 
failed to yield a specific organism and 
may be the result of root conditions 
which appear to be quite unsatisfactory 
on both raspberry and bla&#kberry, as 
described under the former. 
Crown Gall is at present one of the 
most destructive diseases attacking 
raspberries. In some well marked 
cases upon the variety known as 
= Thompson’s Prolific (Bulletin 79) eel- 
Fig. 86. Raspberry stem attacked by An- 
thracnose. This causes “‘birds-eye” spots of the WOrms have been suggested as the 
stems. After Scribner. possible cause of the gall production; 
the leaves of bearing canes whereit will |... 
