Nov. 1907. | THE PRESIDENTIAL ADDRESS. 373 
therefore earnestly hope that the Government will proceed 
further in the right direction, and that we shall have perhaps 
a demonstration forest in the South of Scotland where the 
growth and treatment of hardwoods would receive special 
attention, and a similar demonstration forest in the Highlands 
where the growth and treatment of conifers would more 
fittingly be specialised. Experience in other lands seems to 
prove that the afforestation of extensive areas in Scotland 
can be economically carried out. It would incidentally 
introduce many complementary industries, and might tend 
largely to solve some of the crying problems associated with 
rural depopulation and the crowding into cities and towns of 
the majority of the inhabitants of our land. It has an 
important bearing also on the pressing problem of coast 
erosion. What seems desirable is the scientific and syste- 
matic application of the advice said to have been given by 
the old laird to his son: “Be aye stickin’ in a tree; it’ll 
be growin’ while ye’re sleepin’.” 
IMMUNITY. 
Incidentally the projected experimental work at Inver- 
leiver suggests a subject which I had at one time thought of 
as a suitable topic for an opening address, I refer to the 
important question of the incidence of disease in plants, and 
the work that has been done in the direction of selecting 
individuals that are more or less immune. On the side of 
what may be called the climatic diseases of plants an 
important practical question might be the selection of 
varieties of fruit trees of frost-resisting quality and other- 
wise adapted to our rigorous Scottish climate. It is perhaps 
partly the want of such knowledge that accounts for what 
often seems to me the lesser attention to fruit-growing in 
Scotland compared to England and other countries In this 
connection it is interesting to note the work of Dr. William 
Saunders, who, by crossing the hardier varieties of the 
apple with the Siberian crab apple, obtained new varieties 
specially adapted for the higher latitudes of North America. 
Inverleiver might profitably give opportunity for the practical 
application of discriminating hybridisation in the production 
of new varieties of forest trees and of cultivated fruit trees. 
