PINACEAE 



SuBALPiNE Fir 



Abies lasiocarpa (Hook.) Nutt. 



HABIT. A tree 60-100 feet high and 11^-2 feet in diameter 

 (max. 160 by 3 feet); a dense, narrowly pyramidal, spirelike 

 crown often extending to the ground, with short, thick branches; 

 a prostrate shrub at timber line. 



LEAVES. On lower branches, 1-1% inches long (mostly 

 about 1 inch), flattened, blunt or notched; on upper branches 

 Yl inch long and pointed; deep blue-green; crowded and nearly 

 erect by a twist at their base; stomatiferous on both surfaces 

 (less conspicuous above). 



FLOWERS. Male dark indigo-blue; female dark purple. 



FRUIT. 2-4 inches long, oblong-cylindric, dark purple; 

 scales mostly longer than broad and 3 times longer than long- 

 tipped bracts. Seed: K inch long, with dark lustrous wings. 



TWIGS. Stout, pubescent, and pale orange-brown; becom- 

 ing smooth and gray or silver-white. Winter buds: subglobose, 

 resinous, Vs-K inch long, with light orange-brown scales. 



BARK. Thin, gray, smooth except for numerous resin blisters 

 on young trees; becoming shallowly fissured. 



WOOD. Similar to balsam fir but little used except for fuel. 



SILVICAL CHARACTERS. Tolerant (of its associates, 

 only Engelmann spruce and mountain hemlock are more so) ; 

 growth not rapid; reproduction abundant and vigorous; shal- 

 low root system; lower branches sometimes taking root. 



HABITAT. Canadian and Hudsonian zones; growing from 

 3,500 feet to timber line in the north and from 10,500 feet to 

 timber line in the south; in cool, moist sites; commonly with 

 Engelmann spruce, lodgepole, whitebark, limber, or bristle- 

 cone pines, alpine larch, cork fir, and sapen. 



GENERAL. Corkbark fir A. lasiocarpa var. arizonica (Merr.) 

 Lemm. of New Mexico, Arizona, and southern Colorado, 

 diff'ers from alpine fir in having soft, corky, yellow-white to 

 ash-gray trunk bark. 



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