I i6 TRANSACTIONS OF ROYAL SCOTTIS}! ARBORICULTURAL SOCIETY. 



probably developed in 1915, and it is known that the fructifica- 

 tions disintegrate fairly rapidly after the spores have been shed. 



A careful examination was made of a closely adjoining planta- 

 tion of pure Japanese larch of younger age, but no sign of 

 attack by Phomopsis was discovered. It appears, therefore, that 

 in the area infection was restricted to a certain period, possibly 

 to one season. 



Infection of the Japanese larch by P. Pseiidotsugae has been 

 found in two localities in Scotland, and in both these cases 

 Douglas fir trees attacked by the same fungus were present in 

 close proximity. An examination of the Douglas fir at Jervaulx 

 was therefore carried out, and resulted in the discovery of 

 Phomopsis both on the leading shoots of young trees and on the 

 stems of older specimens, the damage on the latter being very 

 similar to that produced on the Japanese larch. 



At present the conditions under which infection by Phomopsis 

 Pseudotsugae takes place are almost unknown, and much more 

 investigation is required on this subject. As a working 

 hypothesis, however, it may be suggested that the Japanese 

 larch is infected from the fungus present on the Douglas fir, and 

 that this infection only takes place under certain special con- 

 ditions of environment. Malcolm Wilson. 



Professor Sir Isaac Bayley Balfour's Retirement. 



Every member of the Society, we are sure, will join in 

 wishing that our valued fellow-member and illustrious former 

 President, Sir Isaac Bayley Balfour, may long enjoy the best of 

 health and every happiness in the well-deserved rest which his 

 retirement from official duties will bring. 



Among the many prominent members of the Society, who 

 have rendered services of incalculable value to forestry, the 

 name of Sir Isaac Bayley Balfour stands out clearly as the 

 leading pioneer, especially in regard to the teaching of forestry 

 on a scientific basis in correlation with the practical training 

 necessary in the successful application of science to this 

 important industry. 



Sir Isaac became a member so far back as 1877, when the 

 Society was but twenty-three years old. He became President in 

 1890, and during his tenure of office he established a lasting 

 landmark in the progress of forestry, by the inauguration of 



