FUNGI IMPERFECTI 367 



fully as a preventive. Five or more 

 sprayings have been profitable upon 

 American, French, and Japanese 

 stocks, although this has not afforded 

 complete protection. Spraying as for 

 the pear scab is advised when this 

 disease becomes a matter of suffi- 

 cient economic importance in the 

 orchard. 



Fig. 186. Spores of the 

 Entomusporium 



LIV. SOOTY BLOTCH AND FLY SPECK OF THE APPLE AND 

 OTHER PLANTS 1 



Leptothyrium Pomi (Mont. & Fr.) Sacc. 



Clinton, G. P. Notes on Parasitic Fungi. Fly Speck. Sooty Blotch. Conn. 



Agl. Exp. Sta. Rept. (1903): 299-302. 

 Powell, G. H. A Fungous Disease of the Apple. Garden and Forest 9 : 



474-475- 

 Selby, A. D. Sooty Fungus and Fly Speck Fungus. Ohio Agl. Exp. Sta. 



Built. 79: 133-134. 

 Sturgis, W. C. On the Cause and Prevention of a Fungous Disease of the 



Apple. Conn. Agl. Exp. Sta. Rept. 21 : 1 71-175. 



According to the unpublished observations of Floyd the sooty 

 blotch and fly speck are apparently stages of the same fungus. 

 They are almost invariably associated upon the host (Fig. 187), but 

 may occupy distinct areas upon the same portion of the plant. 

 They seem to occur upon the fruit of the apple throughout the 

 limits of its culture. A sooty blotch and a fly speck are also found 

 upon the pear, and along a roadside near Columbia, Mo., there 

 were found more than twenty-five hosts affected by what was 

 apparently the same fungus. These plants were all woody in tex- 

 ture, and the fungus occurred generally on the younger twigs 

 and petioles. The forms upon these hosts may be provisionally 

 referred to as one fungus. Observation indicates that the organ- 

 ism is most abundant under conditions of considerable moisture, 

 half shade, and abundant dust. The market value of apples is 

 affected by the discolorations which result. 



1 For the material of this account I am very largely indebted to unpublished 

 data kindly furnished by Mr. B. F. Floyd of the Fla. Exp. Sta. 



