1908.] TREES AND SHRUBS. 517 



to the scenery. On September 18, at Fort Franklin, its leaves were 

 dropping, and soon afterwards the trees were bare. 



At Fort Simpson it is common and reaches a good size. On June 

 1, 1904, the leaves were just beginning to appear, tingeing the swamps 

 with their beautiful shade of green. As i descended the river the 

 progress of vegetation kept pace in a general way with my rate of 

 travel. At Fort Norman, on June 11, the leaves ami cones of the 

 tamaracks were just appearing, and at Fort Good Hope, ten days 

 later, they were about half grown. The species occurs as a small tree 

 at Fort McPherson, and it is the only tree mentioned by McConnell 

 as growing on the plateau to the westward at an altitude of 1,200 feet, 

 where it attains a maximum diameter of 2 inches and a height of 6 

 or 8 feet. On the Nahanni Mountains, 75 miles below Fort Simpson, 

 it ascends to timberline, at an approximate altitude of 2.000 feet on 

 northern slopes, occurring, of course, as a dwarfed shrub at its upper 

 limit. 



In places the tamarack extends quite to the tree limit. • It was found 

 by the Tyrrell brothers on the Telzoa north to Dubawnt Lake, and 

 by J. W. Tyrrell on Thelon River near its junction with the Han- 

 bury (p. 31 of separate). 



Picea canadensis (Mill.) B. S. P. White Spruce. 



This species, usually called " pine " in the northj is the commonest 

 timber tree of the region, and occurs north to the limit of the forest. 

 Along certain rivers which enter the Barren Grounds from the south- 

 ward the range of this species is extended far beyond its general 

 limits, and sometimes the isolated colonies are of large extent. 



Most of the lumber used in building and general constructive work 

 throughout the region is furnished by this species. Its wood is soft 

 and easily worked, and though admirably adapted for some purposes, 

 is used for others only from necessity. Its slender fibrous roots, split 

 into long strips, are used by the natives to sew together the pieces 

 of birch bark in the construction of canoes and various utensils. Its 

 bark, stripped from the trunks in early spring, forms the usual roof- 

 ing material, taking the place of shingles throughout the region, ex- 

 cept at a few favored posts. A canoe, quickly made from a long 

 section of bark by closing the ends and strengthening the structure 

 with a few T ribs, is often made by the natives for temporary use. 



It reaches its perfection in the alluvial bottoms of the Athabaska 

 and Slave River valleys, but is practically absent from their deltas. 

 In favorable places along Slave River it attains a diameter of 3 feet 

 and a height of nearly 150. On some of the islands in Great Slave 

 Lake, exposed and wind-swept at all seasons, it occurs in a more or 

 less stunted form. On the canoe route between Foil Rae and Great 

 Bear Lake it is common, varying in luxuriance according to the local 

 conditions. Along: the southern shore of Great Bear Lake it forms 



