8oo The Trees of Great Britain and Ireland 



ABIES LASIOCARPA, Rocky Mountain Fir 



Abies lasiccaffa,^uX.^\\,Sylva, iii. 138 (1849); Masters, Gard. Chron. v. 172, ff-/3-27, 32, 

 (1889), and>«r«. Bot xxvii. 129 (1889); Sargent, Silva N. Amer. xu. 113, t. 611 (1898), 

 and Trees N. Amer. 61 (1905); Kent, Veitch's Man. Conifera, 515 (1900). 



Abies bifolia, Murray, Proc. Roy. Hort. Soc. iii. 320 (1863). 



Abies subalpina, Engelmann, Am. Nat. x. 555 (1876). 



Abies arizonica, Merriam, Proc. Biol. Soc. Wash. x. 115, ff. 24, 25 (1896). 



Pinus lasiocarpa, W. J. Hooker, Fl. Bor. Am. ii. 163 (1839). 



Picea bifolia, Murray, Gard. Chron. iii. 106 (1875). 



Picea lasiocarpa, Murray, Gard. Chron. iv. 135 (1875). 



A tree, attaining occasionally 175 feet in height, with a trunk 15 feet in girth, 

 but usually not over 80 to 100 feet high. Bark of young trees smooth and silvery 

 grey ; of old trees shallowly fissured and roughened by reddish brown or whitish 

 scales ; in some trees becoming corky and white in colour. Buds small, about J inch 

 long, ovoid-conical, obtuse at the apex, brownish, resinous ; scales embedded in the 

 resin but roughening the surface of the bud by their raised tips. Branchlets swollen 

 at the nodes, those of the first year ashy grey, smooth, and covered with a 

 moderately dense short wavy pubescence. Branchlets of the second year retaining 

 some pubescence, darker grey, smooth, with the bark slightly fissuring. 



Leaves on lateral branchlets irregularly arranged; sometimes irregularly 

 pectinate with some of the leaves above and below not directed outwards, but 

 forwards at an angle with the axis of the shoot ; usually with most of the leaves 

 directed upwards, those in the middle line above covering the shoot and standing 

 edgeways with their apices almost vertical, a few leaves in the middle line below 

 pointing forwards and downwards. Leaves linear, up to i^ inch long by ^ inch 

 broad, uniform in width except at the gradually tapering base ; apex rounded and 

 either entire or with a slight emargination ; upper surface with a shallow continuous 

 median groove, and with four to five lines of stomata on each side of the groove in 

 its anterior half, the lines fewer in number and broken in the basal half; under 

 surface with two bands of stomata, each of six to eight lines ; resin-canals median. 

 The stomatic lines above give the foliage a glaucous appearance ; the bands below 

 vary very much in whiteness. Leaves on leading shoots closely appressed to the 

 stem with their tips directed forwards, flattened in section, and ending in long 

 slender rigid points. Leaves on cone -bearing branchlets upturned, directed 

 forwards, usually acute and not more than ^ inch long. 



Cones sub-sessile, cylindrical ; rounded, truncate or depressed at the slightly 

 narrowed apex ; 2 to 4 inches long by i J inch in diameter, dark purple and 

 tomentose, with the bracts concealed.^ Scales very variable in size and shape, 

 from f inch long by f inch wide to ^ inch long by i inch wide : lateral margins 

 rounded or with sinuses, usually auricled on each side of the short obcuneate 

 claw. Bract situated at the base of the scale or slightly above it, quadrangular or 



' According to Piper, Contrib. U.S. Nat. Herb. xi. 93 (1906), cones on trees growing in the Olympic Mountains 

 have exserted bracts. 



