54 BOTANICAL SURVEY OF THE CffiUR d'aLENE MOUNTAINS. 



each year. This and the white-barked pine (Pinus albicaulis) are the 

 only trees in these mountains which have a strictly limited lower 



range. 



MERTENS'S HEMLOCK. 

 Tsuga mertensiana (Bong.) Carr. 



A common species and with a regional distribution practically 

 throughout the Cceur d'Alenes. The area upon which it grows most 

 plentifully and attains its largest development is the western portion 

 of the North Fork basin. About 30 per cent of the forest is here 

 composed of this one species. 



Unlike Tattoo's hemlock, it is a tree which belongs to the low, wet 

 valleys, and is rarely seen above 1,400 meters (4,000 feet) elevation. 

 It is of extremely slow growth in most localities. Trees 12 to 15 cm. 

 (4.7 to inches) in diameter, which will count 120 annual rings, are 

 very common. This slow growth is especially marked where the trees 

 are set close. When a larger space intervenes, the trees grow faster 

 and attain greater size. An average height, rarely exceeded, is 40 to 



55 meters (130 to 180 feet), with diameters up to 70 cm. (28 inches), but 

 sometimes groves are found which contain individuals with a diameter 

 of 1.8 meters (5.9 feet). It is usually a very branching tree, with exces- 

 sively long laterals. The crown is about two-thirds the total length. 

 As the tree is often plentiful in accessible localities, it is frequently 

 sawed into lumber. This is of fair quality, and when seasoned it 

 becomes dense and hard, so that a nail can be driven into it only with 

 difficulty. The bark appears to carry a considerable quantity of tannin, 

 and the tree could probably be used as a, source of tan bark. 



YEW. 

 Taxus bri'r'i folia Nutt. 



This species of tree, while classed among the cone bearers, does not 

 produce a cone as its fruit. In the month of August there will be seen 

 in the forests where the species grows a tree, or long, straggling shrub, 

 with evergreen leaves in appearance like those of a fir, and bearing- 

 bright red berries. This is the yew. The tree ranges throughout 

 the Conir d'Alenes, with an extreme altitudinal limit of at least 1,000 

 meters (5,300 feet). It is nowhere abundant; perhaps more nearly so 

 in the North Fork basin than elsewhere. It rarely attains the stature 

 of a tree; more commonly it is a shrub, with long, irregular branches, 

 which sometimes reach a length of 10 meters (33 feet). Near Lake 

 Fend Oreille and in the upper part of the North Fork basin I have 

 seen trees having a height of 20 meters (06 feet) and a diameter of 35 

 cm. (14 inches). Such trees exhibit the characteristics of the species 

 more fully than the shrubby forms. From a specimen of this sort I 

 draw the following description: Height, 20 meters (00 feet); diameter, 



