163 



ish on large trees, very thick and furrowed ; that of the branches rather smooth and 

 glossy. A beautiful tree, of fine ornauieiital appearance, with more or loss silvery- 

 wbite foliage and sharply-tapering crown. 



13. — Balsam Fir. Balm-of-Gtlead Fir. [Abies balsamea^ Miller.) 



A rather small tree growiug in damp or swampy sites of tbe Rocky 

 jMoiiiitains of Idaho and Montana (found also in northeastern United 

 States and north of boundary). It is a short-lived tree, and owing to 

 the small size, lack of strength, hardness, and durability of its wood 

 of little importance as a timber tree; 50 feet in height, and 1 foot or 

 more in diameter; at high elevations much reduced in size. 



Descrlpiion. — Leaves sessile, ^ to 1 inch long, narrow, flat, with small notch at the 

 tip and white lines above, a silvery tinge below ; thickly spreading, somewhat regu- 

 larly in spirals on all sides of the branches, but on horizontal twigs, crowded chiefly 

 on the upper side. Leaf-scars oval, prominent, lasting. Cones 2 to 4 inches long, 

 1 to 1^ inches in diameter, upright on short footstalks (upper branches), cylindrical, 

 tapering slightly ; scales blue-purple, broad, roundish, entire, each with an accom- 

 panying outside bract. Branches chiefly in whorls of about five. 



14. — Balsam. {Abies Subalinna^ Engelm.) 



A tall, slender tree much isolated and rarely forming forests. Gen- 

 erally growing in gravelly soil of slopes and canyons between 4,000 and 

 12,000 feet elevation. Itoccurs in the mountain ranges of Utah, and from 

 Colorado to Montana (westward to Oregon and Washington Territory, 

 and north of United States boundary). It seldom attains qiore than 

 100 feet in height, and from 2 to 3 feet in diameter. The wood is very 

 soft and light, possessing little strength. ^ 



Descripiion. — Leaves of the lower branches usually Jong, narrow, and blunt, in 

 two ranks; those of the upper young branches s7)or^e?", much broader, thicker, acutely 

 pointed, attached by a hroad lase, dense, somewhat in two ranks; whitish beneath; 



to li inches long. Young branches with longitudinal ridges. 



15. — Great Silver Fir. White Fir. {Abies grandis, Lindiey.) 



A very large and important timber tree occurring in Bitter Eoot 

 Mountains, Idaho, and in ranges of northwestern Montana (also on Pa- 

 cific coast from latitude 40° to boundary of United States and north- 

 ward) ; 250 to 300 feet high, with a diameter of 4 to 5 feet. It pre- 

 fers bottom-lands and northern and western slopes below 4,000 feet, 

 but producing the largest timber in the former situations. It is per- 

 haps of greatest importance in the northern Pacific region, where it is 

 said to attain its largest dimensions, and is employed considerably for 

 lumber. The wood, however, is light, soft, and quite inferior to that of 

 the Douglas and Sitcha Spruce. 



Description. — Leaves -| to 1| inches long, narrow, fiat, channeled, blunt, with a, 

 small notch at the tij), comb-like in arrangement, an upper and lower horizontal 

 rank on each .side of the branchlets ; leaves of lower rank much longer; glossy and 

 with two white lines beneath. Cones solitary, 2 to 5J inches long, cjlindrical, on 

 very short footstalks; scale srov/ hroad, entire. Bark scaly and brownish. 



