CHAPTER IX: THE FIRS 



Genus ABIES, Link. 



Trees of pyramidal habit with wide-spreading horizontal 

 limbs bearing thick foliage masses. Wood weak, coarse grained. 

 Bark smooth until quite old, pale, thin and blistered with over- 

 flowing resin vescicles; later, deeply and irregularly furrowed. 

 Leaves usually flat, blunt, 2-ranked, persistent for 8 to lo years, 

 leaving circular scars. Flowers in axillary, scaly cones, pistillate 

 erect on upper branches; staminate on under side of branches 

 lower down on the tree. Fruit annual, erect cones whose scales 

 fall off at maturity; seed resinous.. 



KEY TO SPECIES 



A. Leaves flat and grooved down the middle. 



B. Colour of leaves dark green, shining, with pale linings. 

 C. Scales concealing the bracts of the cones. 

 D. Cones purple. 



E. Leaves straight, 2-ranked, not crowded; 

 bark smooth, brown. 



{A. halsamea) balsam fir 

 EE. Leaves curved, erect on twigs, crowded; 

 bark rough, grey. {A. amahilis) white fir 

 DD. Cones green; leaves about 2 inches long. 



{A. grandis) white fir 

 CC. Scales not concealing the pale green, reflexed bracts 



of the purple cones. {A. Fraseri) balsam fir 

 BB. Colour of leaves pale blue-green. 



C. Cones purple. {A. lasiocarpa) balsam fir 



CC. Cones purple, green or yellow. 



D. Bracts of cone scales concealed; leaves uniformly 



glaucous. {A. concolor) white fir '-^ 



DD. Bracts of cone scales extending into long, whip- 

 like projections; leaves yellow-green, pale 

 below. {A. venusta) silver fir 



AA. Leaves mostly 4-angled, thick, blue-green; cones purple. 

 B. Cone scales covered by pale green, reflexed bracts. 



(A. nohilis) red fir 

 BB. Cone scales covering bracts. {A. magnified) red fir 



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