734 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Canker in Apple-trees. By H. Hasselbring, B.S. (U.S.A. Exp. 

 Stn. Illinois, Bull. 70 ; 4/1902 ; 4 plates). — In America " canker " 

 includes all diseases involving more or less extended areas of the bark. 

 Mention is made of the cankers caused by Nectria ditissima, by 

 Spharopsis Malorum, Peck, and by Gloeosporium malicorticis, Cordley ; 

 but the most serious bark disease in Illinois at present is caused by 

 Nummularia discreta, Tul., which appears usually to be a saprophytic 

 fungus. In Illinois it has assumed the character of a wound parasite, 

 the mycelium finally growing into the wood and causing the death of the 

 branch. If found in its first stages, the diseased portion should be cut 

 away and the wound covered with Bordeaux mixture or paint. All 

 diseased branches should be removed and burnt. The fungus is 

 described and figured (see also Tulasne in " Sel. Fung. Carp. " ii. plate v.) 



F. J. C. 



Canker in Fruit-trees, Cure of. By G. D. Huet (Rev. Hort. 

 p. 212 ; May 1, 1902). — Has succeeded in curing this by removing the 

 rough surface or knots infested and brushing over the bared surfaces with 

 undiluted hydrochloric acid, i.e. the common spirits of salts of commerce. 

 Care as regards clothes and flesh is naturally recommended in using such 

 a corrosive, which, however, while destroying the fungus leaves the tree 

 unharmed. — C. T. D. 



Canker-fung-us on Pinus excelsa. By A. C. Forbes (Gard. 

 Chron. No. 817, p. 185; Aug. 23, 1902).— This fungus known as 

 Dasyscypha resinaria, is a well-known fungus in the United States, it has 

 now been found attacking specimens of Pinus excelsa. It is said that the 

 branches in the early stages of the attack exhibit gouty swellings under 

 the bark, upon which the " cup -shaped fructification appears later 

 on." The blisters much resemble the Larch blisters, which are caused 

 by a very nearly allied fungus. On badly attacked branches the blisters 

 occur at intervals of two or three inches ; the exudation of resin from 

 the affected parts congeals in large masses, and later on completely covers 

 the tree by flowing down its entire length. Cutting down and burning 

 the infested trees seems to be the only practical way of dealing with this 

 pest.— G. S. S. 



Canker, Larch and Spruce (Dasyscypha calycina, Fuckel, and D. 

 resinaria, Rehm). By Geo. Massee (Joum. Bd. Agr. vol. ix. pp. 176- 

 188 ; pis. i.-iii.). — This very valuable article on these destructive diseases 

 is the outcome of observations and experiments extending over a period of 

 sixteen years, and conducted in various parts of England from Yorkshire 

 to Hampshire. 



In this country 1). calycina has also been found on Pinus sylvestris, 

 L., and Abies pectinata, DC. In Southern Europe it has been found on 

 the Pinus Pumilio, Haenke, and in the United States on Abies balsamea, 

 Miller. It has been proved by researches to be a wound-parasite ; " in 

 other words, it cannot gain entrance into the tissues of a living tree 

 except through a wound." 



D. resinaria is apparently more local in its distribution in this country, 



