50 HOUGH'S AMERICAN WOODS. 



year; anthers tipped with a recurved appendage, cells opening lengthwise; fertile flowers 

 in terminal catkins. Fruit, cones maturing the first year, pendulous with scales thin 

 (neither thickened nor furnished with a spur at the apex) persistent on the axis. Other- 

 wise quite as described for the genus Pinus. 

 (Picea is the ancient Latin name.) 



275. PICEA PARRY ANA, SARG. 



BLUE SPRUCE. SILVER SPRUCE. 



Ger., Blaue Tanne. Fr., Sapin Bleu. Sp., Picea Azul. 



SPECIFIC CHARACTERS: Leaves rigid, 4-sided, from % in. on fertile branches to 1% 

 in. long on sterile, curved, spiny, acuminate, bluish green to silvery or dull green ; branch- 

 lets glabrous. Flowers reddish yellow; pistillate with broad denticulate scales and acute 

 bract. Fruit, cones subsessile, oblong-cylindrical, 2y 2 -4 in. long, with glossy rhomboidal 

 flexuose scales narrow and erose-dentate at the elongated apex ; seed % in. long with short 

 wide wing. 



The beautiful Blue Spruce occasionally surpasses 100 ft. (30 m.) in 

 height, and has a trunk diameter of 3 ft. (0.90 m.) or somewhat more, but 

 such, dimensions are unusual. The bark of trunk is of grayish or reddish 

 brown color, fissured into obscure ridges and numerous irregular, closely 

 oppressed scales. The habit of growth of the tree when young is to form a 

 distinct and beautiful pyramid, with horizontal branches in regular whorls, 

 but with advancing age the horizontal branches generally elongate and curve 

 gracefully upward, making an oblong or less regularly pyramidal head. Its 

 various tints of foliage, from green to a beautiful silvery blue, constitute a 

 peculiar and striking feature. In the language of Mr. Enos A. Mills, 

 " With its fluffy, silver-tipped robe, and its garlands of cones, it is the hand- 

 somest tree on the Rockies." . 



HABITAT. - - The Rocky Mountains of Colorado, western Wyoming and 

 eastern Utah between the altitudes of 6,500 and 9,000 or 10,000 ft. above 

 tide, growing mainly along the courses of streams, and generally singly, or 

 in small groups among other trees. It does not form pure stands of any 

 considerable extent. 



PHYSICAL PROPERTIES. Wood light, soft, not strong, of close grain, and 

 yielding a beautiful satiny finish. It is of a brownish white color, with 

 little if any distinction in tint between its sap and heart-woods. Specific 

 Gravity, 0.3740; Percentage of Asli , 0.38; Rein H re Approximate Fuel 

 Value, 0.3726; Coefficient of Elasticity, 553(10; Modulus of Rupture, 454; 



