848 EXPERIMENT STATION RECORD. [Vol.43 



The fungus advances into the surrounding living tissue while the tree is dor- 

 mant, and its attacks may be assisted by the freezing of the stimulated and 

 unripened callus around the canker. A copious flow of gum is associated with 

 the canker development. 



For the control of this disease the author recommends keeping the trees free 

 of all dead and dying wood as much as possible, removing all unnecessary 

 sucker growth during the summer, and destroying rotten fruits at ijicking time. 

 All wounds should be clean cut, and the later in the spring the pruning is 

 done the better the wounds will heal. Large cankers on trunks or main limbs 

 are said to heal if carefully cleaned out during the summer, preferably after 

 a rain. After the treatment the wound should be disinfected with a corrosive 

 sublimate solution and when dry painted with lead paint. 



Fanning strawberries in relation to keeping quality, N. E. Stevens and 

 A. H. Chiveks (Phytopathology, 9 (1919), No. 12, pp. 547-553).— The experi- 

 ments reported were undertaken with the hope of discovering whether under 

 New England conditions fanning wet strawberries would improve their keeping 

 qualities. 



The results are held to offer no evidence in support of the idea that it is 

 injurious to pick strawberries while they are wet. In general, wetting berries 

 which have been picked dry is not to be recommended, but if the berries have 

 been picked wet or for any reason have become wet after picking, the best 

 practice is believed to be immediate shipping without any attempt at drying. 

 In northern and eastern New England the authors found Rhizopus nigricans 

 much less abundant on ripe strawberries than in any of the more southern regions 

 thus far studied. Under New England conditions Botrj'tis seems to be the most 

 common fungus occurring on strawberries. 



Banana wilt, E. W. Brandes (Phytopathology, 9 (1919), No. 9, pp. 339-390, 

 pis. 14, flffs. 5). — This is a detailed account of an investigation begun while the 

 author was connected with the Porto Rico Experiment Station, and concluded 

 as postgraduate work at Cornell and Michigan Universities. Some phases of 

 the work have already been noted (E. S. R., 41, p. 845.) 



Relative susceptibility to citrvis canker of different species and hybrids 

 of the genus Citrus, including the wild relatives, G. L. Peltier and W. J. 

 Feederich (Jour. Agr. Research [U. S.], 19 (1920), No. 8, pp. 339-362, pis. 12).— 

 In a previous publication (E. S. R., 39, p. 757), the senior author gave a pre- 

 liminary report of inoculation experiments carried on under greenhouse condi- 

 tions for a period of six months on the susceptibility and resistance to citrus 

 canker of a number of plants, including some of the wild relatives, citrus fruits, 

 and hybrids of the genus Citrus. In the present report the results are given 

 of continued observations carried on cooperatively by the Alabama College 

 Experiment Station and the Bureau of Plant Industry. U. S. Department of 

 Agriculture, in the summers of 1917, 1918, and 1919, in which both greenhouse 

 and field tests were made. A large number of species and varieties have been 

 sucessfully inoculated, others have proved to be extremely susceptible, while 

 some still show considerable resistance. 



The successful inoculation of a large number of wild relatives in the green- 

 house shows that the organism Pseudomonas citri has a wide range of hosts 

 and is not limited to the gfenus Citrus. In the field, only those wild relatives 

 which were most susceptible under greenhouse conditions were successfully 

 Inoculated. Of tliese Poncirus trifoliata and Microcitrus australis proved to be 

 susceptible, while M. australasica and Fortunella hinclsii are somewhat suscep- 

 tible. So far as the menace of citrus canker to the citrus industry of the 

 United States is concerned, the authors believe that with the exception of 



