THE SPECIES. 39 



moreover, contains a large amount of tannin and is much used in 

 tanning. The wood is usually hard, brittle, and not very durable 

 upon exposure to the weather. The flowers of both kinds occur on 

 the smaller twigs in great numbers, opening early in the spring. 



The western hemlock (Tsuga heterophylla) is found from Alaska 

 southward to northern California, and in the Rocky Mountains to 

 western Montana and northern Idaho. Its range in Montana is 

 confined to a few places in the northwestern portion of the State, 

 in the Flathead Valley, the Glacier National Park, and in the better- 

 watered situations westward. The roots of this tree spread thickly 

 interwoven in the surface layer of the soil, so that the slightest 

 ground fire is fatal to it. The seeds germinate readily upon old 

 rotten logs and stumps and on whatever surface sufficient moisture 

 is retained, and the roots ultimately reach the soil. In regions espe- 

 cially favorable to the growth of this species it is not uncommon to 

 find trees 2 feet or more in diameter, with their roots astride some 

 fallen log, or perched upon a stump 12 or 15 feet high; occasionally 

 the destruction of its early support leaves the tree resting upon stilt- 

 like roots. The young trees spring up in enormous numbers in the 

 deeper forests, and their tops extend characteristically in a more 

 or less horizontal spra t y. 



The western hemlock does not reach its best development in the 

 Rocky Mountains, but in -western Washington and British Columbia, 

 where it reaches a diameter of 5 feet or more and a height sometimes 

 of 200 feet. The wood is useful for many purposes. Large quantities 

 are used in the manufacture of paper. It has, however, no impor- 

 tance in Montana mills. 



The leaves of this species vary a great deal in size, some a fourth, 

 others 1 inch in length, with a median groove on the upper side ; they 

 are thickly produced in alternate arrangement along the slender 

 twigs. The cones are less than 1-inch long and one-fourth to three- 

 eighths of 1 inch in thickness, pendent from the ends of the twigs. 

 The bark is hard and rough, and exceedingly rich in tannin. 



The mountain hemlock (Tsuga Mertensiana}, also called Black 

 Hemlock, is sometimes regarded by botanists as belonging to a dif- 

 ferent genus. It bears, however, sufficient resemblance to the hem- 

 locks to be discussed here. It is a native of the higher altitudes and 

 is found from Alaska through the Cascade range to California, and 

 in the Rocky Mountains to northern Idaho and western Montana. 

 It is found in Montana only in the extreme western portions of the 

 State. It is found at timber line and also at lower altitudes, where 

 it is mixed in larger forests with pine and other species. The tree 

 may attain a diameter of 4 feet, and a height of 60 feet, and bears 

 a dense and narrowly pyramidal crown, the branches of which are 

 sometimes heavily loaded with cones. 



