Larix 397 



Montana to the eastern slope of the Cascade Mountains in Washington and 

 Oregon. 



In British Columbia it is abundant and large in the Kootenay and Columbia 

 river valleys, reaching as far north as the head of Upper Columbia lake, and 

 attaining its most westerly point, where it was found by Prof. Dawson, in long. 

 124° E., on a tributary of the Blackwater river. It grows sparingly about the 

 Shuswap lake and in the Coldstream valley near the head of Okanagan lake. 



The tree, however, attains its greatest development in Montana, where it is 

 abundant and constitutes a great part of the timber of the Flathead, Lewis and 

 Clarke, and Bitter Root Forest Reserves ; and is met with east of Missoula on the Big 

 Blackfoot river. The tree can be most conveniently seen by the traveller on 

 different points of the Great Northern Railway between Nyack and Bonner's Ferry. 

 It attains also great perfection in Northern Idaho and North-East Washington, where 

 it constitutes an important part of the timber of the Priest River Forest Reserve. It 

 also occurs in Oregon, in the Blue Mountains, and on the foothills of the eastern side 

 of the Cascade Mountains,* as far south as Mount Jefferson. 



The western larch occurs between 2500 and 6000 feet altitude ; and attains its 

 maximum height and is most abundant in mountain valleys and on alluvial flats, 

 where the average elevation is 3000 to 3500 feet. On the sides of the mountains, 

 owing to the lack of moisture in the soil, it rapidly diminishes in size and vigour. It 

 requires a wetter soil than either Pinus ponderosa or Douglas fir, and is restricted in 

 its distribution where the rainfall is slight. 



With regard to the opinion, prevalent even in America, that it grows in a semi- 

 arid climate, my experience is entirely different. The meteorological stations are 

 almost invariably in towns in the prairie regions, where the rainfall is small and trees 

 only occur on the banks of streams ; and the maps and statistics of the rainfall give 

 on that account an imperfect picture of the climatic conditions which prevail in the 

 forest regions between the Cascades and the Rocky Mountains. At Kalispell in the 

 Flathead country, which is situated in a treeless plain, surrounded by densely forested 

 mountains, the annual rainfall varies from 13 to 19 inches; whereas at Columbia 

 Falls, placed on the edge of the plain and amidst the larch forests, the rainfall increases 

 to from 20 to 29 inches ; and in the mountain valleys, as at Lake Macdonald and 

 Swan Lake, where Thuya plicata attains a large size, the rainfall must exceed 30 

 inches. The meteorological data of Columbia Falls, which is at 3100 feet elevation, 

 give a fair idea of the climate in which Larix occidentalis thrives, though it is scarcely 

 here at its best. The figures for 1905, which was a dry year, are : — 



' Mr. Cohoon, Forest Assistant in the Northern Division of the Cascade Forest Reserve, wrote to me in 1906 as follows : 

 " The only locality in which larch came under my obsen'ation in the reserve was on the east slope of the Cascade Mountains 

 about 1 5 miles west of Durfur, Oregon. It did not occur abundantly, but was more or less scattered, in mixture with yellow 

 pine, red fir, and lodge-pole pine. It was found on moist but well-drained soil at an altitude of about 2500 to 3000 feet." 

 He adds that he never saw it west of the summit of the Cascades, which he has travelled over from Columbia river to 

 California. 



At Bridal Veil, Oregon, and other places on the Pacific slope, the term larch is erroneously applied to Abies nobilis. 



