CONIFERS. 



SILVA OF NORTH AMERICA. 



79 



the fiercest mountain gales. In such exposed positions it forms low dense thickets, with wide-spreading 

 limbs cHnging close to the ground, hut on more sheltered slopes at lower altitudes it sends up tall 

 and stately stems and sometimes forms nearly pure forests of considerable extent. In southeastern 

 Alaska, where it finds its most northerly home/ the Mountain Hemlock grows on the coast mountains 

 up to elevations of nearly two thousand feet, and occasionally descends to the level of the sea;^ 

 southward It ranges along the coast mountains of British Columbia ^ to the Olympic Mountains of 

 Washington, usually growing only at elevations of more than two thousand five hundred feet above 

 the sea. It is abundant on the western slopes of the Selkirk Mountains in the interior of southern 

 British Columbia, where it is a conspicuous feature in the forests of Tsuga heterophyllay Abies 

 lasiocarpa, Pinus albicauKs^ and Picea Engehnanni ; from the Selkirk Mountains it ranges to 

 northern Montana * and to the Coeur d'Alene and Bitter Root Mountains of northern Idaho ; ^ 

 southward it extends to the Powder River Mountains, and along the Cascade Mountains of "Washington 

 and Oregon, growing with Abies lasiocarpa usually between five and seven thousand feet above the sea 

 on ridges and along the margins of alpine meadows in groves of exquisite beauty,® and pushing the 

 advance guard of the forest to the edge of living glaciers, while at lower altitudes it attains a large size 

 and mingles with Abies amabilis and occasionally with hardy stragglers from the forest of Abies nobilis, 

 which clothes the lower slopes of these mountains^ On the southern part of the Cascade Range it 

 reaches an altitude of eight thousand feet above the sea, and a thousand feet lower and below Crater 

 Lake, In latitude 42° 55', it forms the noblest forest of this Hemlock which has yet been seen, with 

 trees often one hundred and fifty foet In height and from three to five feet in trunk diameter. It is 

 common on Mt. Shasta, In northern California, where it forms extensive groves near the timber-line at 

 eight thousand feet above the sea, and occurs near the high summits of the Siskiyou Mountains, and 

 at an elevation of eight thousand feet on the mountains in the rear of Crescent City ; ^ on the Sierra 

 Nevada it forms groves, usually on northern slopes and between elevations of from nine thousand to ten 



L ■ 



thousand feet above the sea, near the timber-line of all the high peaks, probably finding Its most 

 southerly home in the canon of the south fork of King's River.^ 



The wood of Tsuga Mertensiana Is light, soft, not strong, close-grained, and susceptible of 

 receiving a good polish ; it Is pale brown or red, with thin nearly white sapwood, and contains thin 

 inconspicuous bands of small summer cells and numerous obscure medullary rays. The specific gravity 

 of the absolutely dry wood is 0.4454, a cubic foot weighing 27.76 pounds. It is occasionally 

 manufactured Into lumber.-^** 



^ See F. Kurtz, Bot. Jahrh. xlx. 425 {Fl. Chilcaigebieies). 



The most western point on the Alaska coast where Tsuga Mer- 

 tensiana has been seen is Baranoff Island, where it was first dis- 

 covered and where it grows with Tsuga lieteropliylla and Picea 

 Sitchensis. It probably extends, however, to the neighboring Chi- 

 chagof Island and possibly to the westward of Cross Sound. It 

 is common up to the snow-line on the mountains at the head of the 

 Lynn Canal one hundred miles north of Sitka in latitude 60° north, * 

 the most northerly station from which this tree has been reported 

 (G. M. Dawson, Garden and Forest, i. 59; Rep. Geolog. Surv. Can. 

 n. ser. iii. pt. i. Appx. i. 189 B. — Macoun, Mej). Geolog. Surv. Can. 

 n, ser. iii. pt. i. Appx. iii. 226 B). 



2 The only stations at the sea-level for this tree which are known 

 to me are Baranoff Island and the shores of Yes Bay in latitude 

 55° 54' north, where it was first collected by Mr. M. W. Gorman. 



8 Macoun, Garden and Forest, ii. 525 ; Cat. Can. PL pt. iv. 362. 



* Tsuga Mertensiana was found in northern Montana by Mr. 

 H, B, Ayres in September, 1893, on the divide between Thompson 

 and Little Bitter Root Creeks, at an elevation of between six and 

 seven thousand feet above the sea-level. 



6 Tsuga Mertensiana appears to have been first noticed in Idaho 



by Mr. Serene "Watson, who found it in 1880 on the Lolo Trail 

 toward the northern extremity of the Bitter Boot Range. In Idaho 

 it is confined to the high divides of the Bitter Root and Coeur 

 d'Alene Mountains from that of the Clearwater River on the south, 

 where it is said to form more than seventy-five per cent, of the 

 forest growth, northward to the upper St. Joseph and to the divide 

 between the St. Joseph and Cceur d'Alene Rivers, being more abun- 

 dant on the Clearwater and the St. Joseph than farther north. 

 (See Leiberg, Contrih. U. S, Nat. Herb. v. 53.) 



^ In August, 1896, I found Tsuga Mertensiana growing with 

 Tsuga heterophylla on the east slope of the Cascade Mountains of 

 Washington, near the mouth of the Cascade tunnel on the line of 

 the Great Northern Railroad, at the remarkably low elevation of two 

 thousand two hundred feet. 



^ See Piper, Garden and Forest, iv. 382, f. 63 ; also Garden and 

 Forestj x. 1, f . 1, 2. 



^ Teste A. J. Johnson. 



^ Teste John Muir. 



^0 The inaccessibility of the alpine slopes which are the usual 

 home of this tree has protected it from the lumberman, although 

 the wood has considerable value for purposes of construction. On 



