418 



MANUAL OF FRUIT DISEASES 



responsible for marked decrease in production such as late 

 frosts, poor management and age of plantations. It reduces the 

 crop by reducing the number of fruit-spurs. Buds are killed and 

 leaves may die. From 2 to 50 per cent of the canes are lost 

 through their brittleness; for when brittle they break easily 

 while being put down in the fall or taken up in the spring. In 



New York the disease is far less 

 injurious than in Colorado. 

 Symptoms. 



The disease is first apparent in 

 July. The lesions, one to several 

 on a cane, are sharply defined, con- 

 spicuous, and measure from one to 

 tfour inches long and may half-way 

 girdle the cane (Fig. 122). Spots 

 are found on the nodes near the 

 ground. They may also occur on 

 the internodes and petioles of the 

 I leaves. An area about the buds at 



the base of the leaves becomes 

 brown, the buds shrivel and become 

 dry. The buds then are either 

 weakened considerably, so that they 

 make only feeble growth the follow- 

 ing spring, or they die. In the 

 former case the buds come out, but 

 are small, soon turn yellow, and die. 

 On account of this disease fruit-spurs 

 may not be found for two feet above the ground. However, 

 berries are produced on the upper half. Lesions on the nodes 

 and internodes may coalesce so that the whole lower portion 

 of a cane may become dark. The affected bark splits lon- 

 gitudinally, thus allowing the cane to dry out prematurely. As 

 a result of this desiccation the cane is more brittle than 



FIG. 122. Spur-blight of rasp- 

 berry. 



