CHAPTER VI. 
CONDITIONS AFFECTING THE GEOGRAPHICAL DISTRIBU 
TION OF PLANTS AND TREES IN NORWAY. 
In Norway, as is the case everywhere, the distribution of 
forests, and of different kinds of forest trees, is effected, and 
I may say determined, by conditions varying in different 
districts, predominant amongst which are heat and mois- 
ture, and wind and soil. 
From a knowledge of the natural history of different 
kinds of trees there may be learned much in regard to 
these conditions in the several localities in which they grow, 
much more than can be stated and proved in a few words, 
for it is not simply the sum of different measurements 
such as are applicable to these conditions, but the reflex 
aud complicated influence of one and another of these upon 
one and another of them, upon which the ultimate result 
depends,—and on variations in some of them at different 
periods, embracing, amongst others, the periods of the 
germination of the seed, of the expansion of the leaf, of 
the formation of the flower, of the casting of the pollen, 
and of the maturing, and the falling of the fruit. By 
stating, however, the characteristics of different localities 
in connection with these conditions, there may be made a 
contribution towards a collection of facts which may be 
interesting to the general reader, and not without value 
to some youthful student of forest science; and this I 
shall attempt, citing and translating facts embodied in the 
report by Dr. Broch, to which I am indebted for much of 
what I have advanced in regard to the geographical dis- 
tribution of the trees, 
‘Speaking generally,’ says Dr. Broeh, ‘the Norwegian 
flora presents little variety. The gneiss, granite, and 
