RASPBERRY DISEASES 399 
REFERENCES ON Crown-GALL 
Swingle, D. B. Fruit diseases in Montana.. Crowngall of raspberry 
and blackberry. Montana Agr. Exp. Sta. Cire. 37 : 326-327. 1914. 
Selby, A.D. A brief handbook of the diseases of cultivated plants in 
Ohio. Raspberry crown gall. Ohio Agr. Exp. Sta. Bul. 214: 
437-488. 1910. 
Selby, A. D. Some diseases of orchard and garden fruits. II. Dis- 
eases of raspberries and blackberries. 5. Crown gall. Ohio 
Agri. Exp. Sta. Bul. 79: 108-112. 1897. 
OraANGE-Rust 
Caused by Gymnoconia interstitialis (Schl.) Lag. 
This is a well-known raspberry and blackberry disease over 
the eastern United States and southern Canada. It also occurs 
as far south as Florida and California. The disease is found in 
Europe and Asia commonly. 
The attacks are limited to wild and cultivated blackberries 
and raspberries. It is extremely common on black raspberries 
in New York. In Illinois the Snyder is said to be resistant. 
On all of these forms the disease is variously referred to as 
orange-rust, spring-rust, red-rust, bramble-rust, and erroneously 
as yellows. The disease destroys the usefulness of the leaves 
and they finally fall. Annual recurrence of this phenomenon 
results in rendering the plants worthless. Rarely do affected 
plants recover. Ten per cent rusty plants are frequently 
reported. Twenty-five per cent or more are recorded. In 
some localities the orange rust has so seriously affected rasp- 
berries and blackberries as to make their cultivation unprofit- 
able. 
Symptoms. 
First signs of the disease are observed in the spring — whence 
the name spring-rust. In April and May, even before the 
leaves are entirely unfolded, evidences of the disease may be 
seen. On the upper surface of the leaves glandular bodies are 
