FOREST TYPES OF THE COEUR D'ALENE MOUN- 

 TAINS AND THEIR DETERMINING FACTORS. 



Professor Wm. W. Morris. 



The Coeur d'Alene mountain country of northern Idaho 

 is one of marked topographic features. It is a country of 

 steep slopes, narrow ridges, and narrow canyons. Such sharp 

 features as these produce two well defined regions of vastly 

 dissimilar site conditions, and as a result over each of these 

 regions the principal tree species found are entirely different. 

 These great general types, therefore, the result of the above 

 mentioned marked physical factors, are quite distinct ones and 

 are bounded by fairly sharp and clear lines. In this respect the 

 Coeur d'Alene country is quite different from a more level 

 country. In the latter there is usually a gradual transition from 

 one type to another due to the fact that there is no marked line 

 of physical change to produce a corresponding marked effect on 

 the plant societies within its environs. 



The climate of the Coeur d'Alene country is a fairly moderate 

 one. The temperature rarely falls much below Fahrenheit and 

 the summers are seldom extremely hot. In the higher river bot- 

 toms frost may be expected almost any month of the year. This 

 condition limits the crops which can be raised in these narrow 

 valleys mainly to root crops and hay, both of which do exceed- 

 ingly well. The annual precipitation of the region is approxi- 

 mately forty inches. 



The soil is in general deep and rich. One analysis made 

 from a small area showed an abnormal amount of phosphorus 

 present. The soil might be described in general as a silty loam, 

 the result of disintegrated quartzite rock. 



Owing to the fact that the ruggedness of the country makes 

 impossible the use of the plow and that the climate limits the 

 productivity of the land for agricultural purposes, we have in 

 the Coeur d'Alene mountains a permanent forest area splendidly 

 adapted for raising timber of a high commercial value. 



THE FOREST TYPES. 



A large part of this region can be divided into two great 

 types, namely, the western white pine type and the Douglas fir 



