1919] DISEASES OF PLANTS. 157 



Tlie disease is apparently of fungus origin. Isolations were repeatedly made, 

 and inoculations from pure cultures on apple, pear, rose, blackberry, plum, and 

 peach twigs kept in test tubes resulted in rapid growth and the development of 

 conditions identical with those observed in the natural canker. No attempts 

 were made to produce the disease on trees in the open, as it was feared from the 

 rapid development made that the disease might occasion serious loss. 



The fungus which causes the disease is said to belong to the genus Cytospora, 

 but it has not been specifically identified owing to the confusion between the 

 species of this and closely allied genera on various rosaceous hosts. Lists are 

 given of about 90 species of Valsa and Cytospora which have been reported on 

 various species of Rosacea;. 



A bibliography of the literature completes the publication. 



Peach diseases, T. F. Manns (Delaware Sta. Bui. 122 {1918), p. SO). — ^A brief 

 account is given of inoculation work with peach yellows and little peach in 

 the experimental orchard. Natural infection through bruising and rubbing, as 

 by harness, etc., from infected trees to healthy trees was not found to bring 

 about a great amount of infection. The author records the complete recovery 

 of two out of five trees which were inoculated with yellows in 1916 and showed 

 typical symptoms of the disease in 1917, two recovering completely in 1918. 

 Two of the trees of this series are reported as dead and another nearly so. 



Placing tree protectors around trees to keep away borers has given very poor 

 results. 



Wood rots of peach trees caused by Coriolus prolifLcans and C. versicolor, 

 J. A. Elliott {PhytopatJwlof/y, 8 (WIS), No. 12, pp. 615-617, figs. 2).— Parasitic 

 wood rots of peach trees due to C. prolificans and C versicolor are described by 

 the author as occurring near Lamar, Ark., on peach trees that had been rather 

 severely cut back. The parasitLsm of the fungi was considered evident, as the 

 trees had made a vigorous growth for one or two seasons following the cutting 

 back and had then been checked by the destruction not only of the heartwood 

 of the ofder trees but of the sapwood as well. The destructiveness of the rots 

 is said to have been limited to certain localities, the orchard in question being 

 on relatively low, heavy soil, while in other orchards in the vicinity, on higher 

 ground and lighter soil, trees which had been cut back in a similar way showed 

 no signs of the rot. 



A Sterigmatocystis smut of figs, R. W. Hodgson {Phytopathology, 8 (1918), 

 No. 10, pp. 545, 546).. — The author states that California growers of White 

 Adriatic figs have experienced losses due to a black discoloration of the fruit. 

 A survey was made of some of the packing houses and a considerable quantity 

 of infected figs was found. Cultures made from such figs have miiformly 

 shown the presence of a Sterigmatocystis. The percentage of badly infected 

 fruit is relatively small, but a larger percentage is infected to a slight extent. 

 When opened, these figs show a streak or two of a black, gummy nature which 

 greatly detracts from the appearance of the figs. The gummy masses in small 

 quantity are said not to injure the flavor of the fruit, and such figs can be 

 used in the manufacture of fig paste. The fungus is said to be the same as 

 that causing the internal rot of pomegranates previously described (E. S. R., 28, 

 p. 549). 



The prevailing practice in preparing dried figs is to allow them to remain 

 on the ground for 10 days or 2 weeks. The author believes that gathering the 

 fruit at shorter intervals, while resulting in a much better dried fig, will also 

 prevent at least a certain amount of black smut. 



Early occurrence of citrus scab in Japan, H. A. Lee {Phytopathology, 8 

 {1918), No. 10, p. 551). — The author notes the occurrence of citrus scab lesions 



