White Spruce 



55 



Leaves not glaucous; cones early falling. 

 Leaves glaucous; cones long persisting. 

 Western trees. 

 Cone-scales very blunt; cones 2 to 4.5 cm. long; twigs smooth. 

 Cone-scales rhomboid, more or less acute; cones 5 to 10 cm. long. 

 Twigs hairy; leaves not stiff. 

 Twigs smooth; leaves stiff. 

 Leaves flattened. 



Twigs hairy; leaves blunt-pointed. 

 Twigs smooth; leaves sharp-pointed. 



2. P. rubens. 



3. P. Mariana. 



4. P. alhertiana. 



5. P. Engdmannii. 



6. P. pungens. 



7. P. Breweriana. 



8. P. sitchensis. 



I. WHITE SPRUCE — Picea canadensis (Miller) B. S. P. 

 Ahies canadensis Miller. Picea alba (Aiton) Link 



Also called Single spruce, Skunk spruce, Cat spruce, Double spruce, and 

 locally known as Spruce and Pine, this extends across the entire northern portion 

 of the continent, if the western tree is, as sup- 

 posed to be, identical with the eastern, from New- 

 foundland and Labrador to Alaska; eastwardly 

 its southern limits are in South Dakota, penin- 

 sular Michigan to northern New York, reaching 

 the Atlantic coast in southern Maine. It attains 

 its greatest development in northern British 

 America, a maximum height of about 35 meters 

 with a trunk diameter of i meter. In its 

 eastern range, however, it seldom reaches half 

 these dimensions. It prefers moist hillsides or 

 the borders of rivers or swamps. 



The branches are long, stout, and upwardly 

 curved, their branchlets stout, sti£f, and pendu- 

 lous. The bark is 6 to 12 mm. thick and 

 broken intg irregular scaly plates which sepa- 

 rate easily and are light brownish gray. The twigs are nearly smooth, grayish 

 green becoming orange-brown and finally dark grayish brown. The winter buds 

 are broadly ovoid and blunt, from 3 to 6 mm. long, their scales light brown and 

 fringed. The leaves, which sometimes have a pronounced polecat odor, are 

 4-sided, i to 2 cm. long, sharply stiff-pointed, light bluish green or grayish at 

 first, becoming pale blue or blue green with age and marked by several rows of 

 stomata on each surface; they are crowded toward the upper side of the twigs by a 

 twist of the under ones, incurved and point toward the end of the twig, those of the 

 fertile branchlets being about half the length of the others. The staminate flowers 

 are oblong-cylindric, 1.5 to 2 cm. long, reddish, becoming yellow, and borne on 

 long slender stalks. The pistillate flowers are of similar shape, a little longer, 

 pale reddish or yellowish green and sessile. The cones are nearly sessile, oblong- 



FiG. 42. — White Spruce. 



