140 MASSACHUSETTS HORTICULTURAL SOCIETY 



fall off. The most easily distinguishable symptoms of this disease 

 are on the seed pods. Infected pods lose their green color, become 

 shriveled, and are soon covered with salmon-colored patches which 

 cannot fail to attract attention. The cause of the anthracnose 

 is the fungus Glomcnila rufomaculans. This fungus causes also 

 the bitter rot of apple and the ripe rot of grapes. Cross inocula- 

 tions have definitely proven that the fungus can go back and forth 

 from the apple to the sweet pea and vice versa. x\nthracnose 

 begins its destructive work early, even in the seedling stage, this 

 sometimes being the case in greenhouse conditions. In field con- 

 ditions the disease starts about July 1, when the plants are in their 

 bloom and in the prime of beauty. This is also the time when the 

 bitter rot disease of the apple makes its appearance in the orchard. 

 The fungus is carried over winter on cankered limbs and mummied 

 fruits of diseased pods and seeds of the sweet pea and also in the 

 soil. Anthracnose is a field disease which thrives in practically 

 every season. It is favored as much by wet summers as by hot 

 dry months with abundance of dew at night. 



Streak, Bacillus lathy ri Manns and Taub. 



The cause of streak is an organism scientifically known as Bacillus 

 lathy ri Manns and Taub. Next to anthracnose, streak is a very 

 serious disease, which cannot be taken too lightly. Until recently 

 it was thought that streak was confined to outdoor sweet peas. 

 Recently, however, the writer has found this to be a serious disease 

 of the greenhouse peas. 



The disease was first observed, according to a letter from Mr. 

 T. A. Weston, of Orpington, England, by H. J. R. Digges, of 

 Dublin, in 1904 or 1905. In the fall of 1906 Mr. Weston states he 

 had a note of the disease in the Gardener's Chronicle, describing it 

 as a "new disease under the title of 'Streak.'" In 1908 George 

 Massee, in a letter to a correspondent who had sent in diseased 

 specimens, replied, " the disease is of a physiological nature." 



So far as we have been able to obtain literature, it appears that 

 only since the summer of 1908 has any definite work been done 

 upon the disease. Chittenden, in England during 1908, 1909, 



