Leaf-Spots 257 



Studies made at the Geneva, New York, Experiment Station have 



shown this to be a mistake. 



References. 



Geneva, N. Y., Expt. Sta. Bull. 226. 



Colorado Expt. Sta. Bull. 206. 



BLUE-STEM OF BLACK RASPBERRY 



Acrostalagmus caulophagus, Lawrence 



This is a disease which has proved very destructive on the Pacific 

 Coast, especially in Washington. It first appears on the canes, 

 which become discolored and dark, or rarely blue-black. It is most 

 conspicuous toward the base and on the most vigorous plants. On 

 the young shoots the blue-black color may spread over the entire 

 shoot in the course of a few days. The leaves wilt and turn yellow, 

 then brown. The fruit only partially develops and is dry, coarse 

 and tasteless. The fungus may gradually work its way back into 

 the roots, causing a reddish or brown discoloration of the wood. 

 It is thought to live over winter in the soil and enter the plant at 

 the crown, working upward. It has also been found on the roots 

 of red raspberry and blackberry but is not common there. It is 

 very destructive at times and may cause a loss of a considerable 

 portion of the crop. 



Little definite experimental work appears to have been done in 

 trying to control it. Spraying, so far as tried, seemed to be of no 

 value. 

 Reference. 



Wash. Expt. Sta. Bull. 108. 



LEAF-SPOTS 



Several species of fungi attack the leaves of brambles, causing 

 leaf -spots. Among the more common and best known are Septoria 

 Rubi, West., with two botanical varieties and Cylindrosporium Rubi, 

 Ell. and Morgan. 



These two species differ in their botanical characters but are 

 very similar in their general appearance on the leaves. Both cause 

 small brown or light-colored spots, and when abundant may do harm 



