
THE SYLVA OF MONTANA. 411 
shade until in the rich moist bottom-land the tree is one. 
hundred and fifty feet high and over four feet in diameter. 
This is the true A. grandis, and the same as grows along 
the Lower Columbia, while a middle form occurs sparingly 
about Puget's Sound, and was referred to by me in a former 
report as possibly being the true A. taxifolia, for which see 
the notes on Abies JDouglassii. The dense growing, white- 
barked variety (amabilis), attains three feet in diameter, 
and one hundred feet in height, on the east slope of the 
above-named mountains. i 
Doverass, og Rep Fir (Abies Douglassii). This spruce 
exhibits nearly as much adaptability to all circumstances 
as Pinus ponderosa, which it accompanies throughout the 
Rocky Mountains, but is much less abundant in the drier 
situations than that, and more so on the moist Cœur d'Alene 
Range. It varies in the color of the bark, length of cones, 
leaves, etc., as might be expected in so many localities. * 
The young shaded tree, growing in the moistest spots, has 
leaves an inch and a half long, shining, and the bark smooth 
and white, so that only the single arrangement and more lax 
growth distinguish it from young trees of A. grandis. This 
is doubtless the true A. taxifolia, as before suspected, and 
loses its distinetness of character with age. This form, with 
Very long slender leaves and cones, prevails mostly on the 
West slope of the Cœur d’Alefie, Cascade and Coast ranges, 
Where there is most rain. The largest Rocky Mountain trees 
do not quite equal some of those on the Lower Columbia. 
It is the only spruce I saw from Fort Colville to the Spo- 
kan river, where its range is stopped by the Great Columbia 
Plain. It reappears at the Dalles, and probably also on the 
Blue Mountains. 
After observing these conifere, and other trees also, for 
Some time, the eye learns their general habit so well, that - 
there is usually no difficulty in distinguishing species at 
Sight, and at a considerable distance off. 
wp rows on the first mountain range, nearly as far east as Milk river, to longitude 

