Evergreen conical trees, with linear short more or less 4-sided leaves spreading in all directions, joined at the base to short sterigmata, quickly falling when dry. Cones ovoid or oblong, obtuse, pendulous, the scales numerous, thin, obtuse, persistent.

Fig. 4. Picea glauca

Fig. 4. Picea glauca.

a.

Cones usually less than 5 cm. long

b. Twigs glabrous b. Twigs pubescent

1.

P. glauca

c. Leaves 12-15 mm. long; Appalachian

2.

P. rubens

c. Leaves usually 6-10 mm. long; chiefly Canadian

3.

P. mariana

a.

Cones 10-15 cm. long

4.

P. abies

1. P. glauca (Moench.) Voss. White Spruce. A handsome tree to 45 m. high, 4-6 dm. in diameter; bark pale brown;branch-lets glabrous; leaves slender, pale or glaucous, 8-18 mm. long; cones subcylindrical, about 5 cm. long, the scales pale, thin, with an entire edge. Rich woods, Labrador to Alaska, south to South Dakota and New York; typically a Canadian tree (Fig. 4).

2. P. rubens Sarg. Red Spruce. (P. rubra Dietr.). A slender tree 20-35 m. high, 6-9 dm. in diameter; bark reddish, roughened by thin irregular brown scales; branchlets pubescent; leaves slender, 12-15 mm. long, somewhat acute; cones maturing the first year, deciduous in autumn or during the winter, elongate-ovoid, 3-4 cm. long, brown, the scales rounded, entire, or slightly erose at the tip. Woods, Prince Edward Island to Ohio, south on the mountains to North Carolina and Tennessee; typically an Appalachian tree (Fig. 5).

3. P. mariana (Mill.) BSP. Black Spruce. Bog Spruce. Usually a small tree less than 30 m. high and 2-3 dm. in diameter; bark broken into flaky gray or reddish scales; branchlets pubescent; leaves short and thick, mostly 6-10 mm. long, pale bluish-green with a white bloom; cones short-ovoid or globose, 2-3 cm. long, dull grayish-brown, the scales erose. Cool slopes and bogs, Labrador to Alaska, south to Alberta and Pennsylvania, with scattered colonies in the mountains of Virginia; typically a Canadian tree (Fig. 6).

Fig. 5. Picea rubens

Fig. 5. Picea rubens.

Fig. 6. Picea mariana

Fig. 6. Picea mariana.

Fig. 7. Picea abies

Fig. 7. Picea abies.

4. P. abies (L.) Karst. Norway Spruce. (P. excelsa Link). A tree to 50 m. high, with drooping lower branches; bark reddish-brown; buds reddish or light brown, not resinous; branchlets nearly glabrous; leaves slender, sharp-pointed, dark-green, glossy; cones 1-1. 5 dm. long. Introduced from Europe as a shade tree, spreading slightly from cultivation in the northern section(Fig. 7).