1908.] TREES AND SHRUBS. 525 



Alnus alnobetula (Ehrh.) Koch. Mountain Alder. 



This alder occurs throughout the region from the Saskatchewan 

 northward to the tree limit. It is abundant on the Athabaska Land- 

 ing road, and appears here and there along the water route north to 

 (ircal Slave Lake, though usually less common than the hoary alder. 

 North of Great Slave Lake it is the predominating alder, and on the 

 canoe route between that body of water and Great Bear Lake, and 

 along its shores, was the only alder detected. It was also the com- 

 mon species on the Mackenzie north to the delta. At Fort Simpson, 

 in 1904, its buds began to swell about March 30, its catkins opened 

 on April 23, and its leaves began to unfold on May 20. The leaves 

 were in about the same condition at Fort Norman on June 11. 



A specimen H inches in diameter, growing on the shores of a large 

 lake a few miles south of MacTavish Bay, had 23 annual rings. 



The alders seen by Hanbury on upper Dease River a were undoubt- 

 edly this species. In the region east of the Mackenzie system it 

 was found by the Tyrrell brothers as far north as Carey Lake and 

 Ferguson River. 



Alnus incana (Linn.) Willd. Hoary Alder. 



This alder is the more common of the two species north to Great 

 Slave Lake, and occurs along the Mackenzie north to Peel River. It 

 was not detected on the canoe route followed between Great Slave 

 and Great Bear lakes. 



An infusion of the inner bark of the alders, the bark being first 

 broken up by chewing, is used by the Indians to stain dressed caribou 

 skins, the resulting color being a bright tan. Otherwise the alder is 

 of little economic importance to the native tribes. 



Ribes oxyacanthoides Linn. Northern Gooseberry. 



This is the commonest representative of the genus throughout the 

 region, being especially abundant in the vicinity of the trading posts, 

 where it often forms dense thickets. About Athabaska Lake its leaves 

 open about the first of June, its blossoms appear about the same time, 

 and the fruit ripens about the first of September. Farther north it 

 flowers considerably later, but matures its berries at about the same 

 date. Near Leith Point, Great Bear Lake, on September 8, 1903, its 

 leaves had turned red and its fruit was well developed and fully ripe. 



At Fort Simpson, on May 8, L904, its leaves had just sprouted; on 

 May 21 the flowers had appeared; and on May '_! ( .> the leaves were 

 about half developed. 



The berries of this gooseberry are well flavored and are gathered 

 by all the Indian tribes within its range. 



"Spoil and Travel in Northland of Canada, p. 239, 1904. 



