NOTES AND QUERIES. 73 



NOTES AND QUERIES. 



A Newly-recorded Disease on Japanese Larch, caused 

 BY Phomopsis Pseudotsugae. 



On nth August Mr George Leven, Bowmont Forest, wrote 

 to say that he had observed certain symptoms of disease on 

 dominated stems in a Japanese larch plantation last autumn. 

 At that time it did not seem to be of a serious nature, but 

 continued observations had now convinced him that the matter 

 was really serious, as a larger number of stems than had been 

 observed during the earlier part of the growing season were 

 now showing patches of sunken cortex, and during the last week 

 or two the outflow of resin made these more conspicuous. 

 From his knowledge of Phomopsis on the Douglas fir, he was of 

 opinion that the present symptoms shown by the Japanese larch 

 were due to the same cause. 



Similar symptoms of disease had been pointed out to the 

 members of the Society on their recent visit to Yorkshire. 

 The matter appeared to be one which required immediate 

 investigation. Without loss of time a specimen was obtained 

 from Mr Leven, and this was submittted to Dr M. Wilson at the 

 Royal Botanic Garden, who reports as follows, under date 

 23rd August 192 1 : — 



^'■Report on Specimen of Japanese Larch. — The specimen 

 forwarded by Mr George Leven consists of about 6 feet of the 

 trunk of a Japanese larch 2-2^ inches in diameter, and showing 

 twelve annual rings at the lower end. It is attacked by a fungus 

 which appears to be identical with Phofnopsis Pseudotsugae. 



"Two depressed areas are present on the bark, one near the 

 base and the other towards the upper end. These, which are 

 darker in colour than the normal bark, are elliptical in form 

 and measure lo-ii inches in length and about 5 inches across; 

 they therefore extend about three-quarters of the distance round 

 the stem. The boundaries of these areas are marked by the 

 exudation of considerable quantities of resin. There is a large 

 number of small black fructifications on the depressed areas ; 

 these emerge through small slits in the bark which are elongated 

 in a direction at right angles to the longitudinal axis of the stem. 

 The fructifications, which are up to i mm. in diameter, are of 



