328 



Bulletin 263. 



I- 



■( 



^. / 



(d). Leaves of nearly normal size showing a blanched or chlorotic 

 condition and often crimped about the margin. 



^^ (e). Apparently healthy vines with leaves 



and fruit shriveling away and dying in the 

 middle of or late in the summer. 



(f). The presence of fleshy or corky ex- 

 crescences on the stem and arms during the 

 summer ; in the autumn these dry down and 

 become reddish brown and the following spring 

 slough off. They have somewhat the appear- 

 ance of new growth to heal a wound and are 

 in longitudinal ribs, 1-6 inches long; globose, 

 tumorous bodies 5^-3 inches in diameter, on 

 one side of the stem, or a gnarled growth 

 encircling the stem near the base (Figs. 44, 45, 

 46,47). 



(g). The presence of minute black pimples, 

 fruiting bodies of a fungus, on a dead spur, 

 on dead bark or on dead wood under the bark. 



(Fig- 50.) 



(h). The presence of small reddish brown 



spots on the green shoots (Fig. 48). The 



spots may be one-eighth of an inch in diameter 



and distinct ; anastomosed to form a continuous 



diseased area sometimes extending for an inch 



or more up and down and half-way round the 



shoot ; or in narrow, v-shaped, longitudinal slits. 



(i). Any of the above conditions may refer 



to one arm only, and any vine may show only 



a few to nearly all of the conditions named. 



(Fig. 49-) 



NAME OF THE DISEASE 



This disease has been called Anthracnose by 

 Atkinson ('04). Selby and Van Hook ('07) 

 refer to it as localized stem blight. From an ex- 

 amination of the brief descriptions it seems not 



Photo. Sept. 7, 1907 



Fig. 44. — Co-ncord. Excres- 

 cences on a main stem of 

 a seven-year-old vine 



('04) Atkinson, G. F. Anthracnose of the Grape. 

 Agr. Exp. Sta. of the Coll. of Ag.. Cornell 

 Univ. Press Bulls. I and 2, April 25, 1904. 



(•07) Selby, A. D. & Van Hook, J. M. (1. c.) 



