Forests of the Yukon Territory. 67 



creases in size below and above this elevation, and becomes dis- 

 torted and scrubby at tree line. 



Between the Pelly river and the north fork of the ^NlcOues- 

 tion the timber line has been variously estimated at from 4,200 

 to 4,700 feet above sea level. In these localities the only tree 

 represented was the balsam, the spruce generally disappearing a 

 few hundred feet below. 



In the Klondike district, timber line only reaches an eleva- 

 tion of 3,500 feet above sea level. The last tree seen here is the 

 spruce, balsam being altogther absent. 



The poplar (Popuhis balsamifera) grows on the islands and 

 alhivial flats of the main rivers ; it occurs mixed with the spruce, 

 or in thin fringes along the gravel bars, and in small forest groves. 

 It is seen in all stages of growth from a small shrub to a consider- 

 able forest tree. It gives out an agreeable and refreshing odour 

 during the early summer ; it is also known as the " balm of 

 Gilead." 



The aspen is specially characteristic of dry, open grassy hill- 

 sides facing southward, of which there is a great extent on the 

 Yukon, Pelly and Stewart valleys. 



The birch in the Yukon Territory never forms extensive 

 groves, but grows singly or in small grovps with the black and 

 white spruce. Most of the birch is small, being mere poles, but 

 one species {Betula resinifera) sometimes attains a diameter of 

 eight or even ten inches and is valuable for stove wood. 



The willow, being the principal food of the moose, rarely at- 

 tains the size of a forest tree, but occasionally willow trees are 

 seen in the neighborhood of old Indian villages. 



In the spruce forests of the valleys, dry willow trees are 

 found entangled in the living spruce in great quantity. These 

 willows are often three or four inches in diameter and ten to 

 twenty feet high. They evidently protected the spruce seedlings 

 but were finally overshadowed by them. This supply of drv 

 wood is of great benefit to the voyageur as it ensures a good 

 camp fire in wet weather and during winter travel. 



The most widely distributed shrub is the dwarf birch {Betula 

 glandulosa), it grows densely on portions of the mountainous 



