Y. 2, THE BLACK OR DOUBLE SPRUCE. 81 
Sp. 2. ‘Tue Brack or Dovste Spruce. Abies nigra. Michaux. 
Figured in Lambert’s Pinus; Plate 37. 
Michaux ; Sylva, III, Plate 147. 
The two species of spruce, the black and the white, or, as 
they are more commonly called, the double and the single, are 
distinguished from the fir and the hemlock, in every stage of 
growth, by the roughness of the bark on their branches, pro- 
duced by little ridges, running down from the base of each leaf, 
and by the disposition of the leaves, which are arranged in spi- 
rals equally on every side of the young shoots. 'The double is 
distinguished from the single spruce, by the darker color of the 
foliage, whence its name of black spruce, by the greater thick- 
ness, in proportion to the length, of the cones, and by the loose- 
ness of the scales, which are jagged or toothed on the edge. 
The trunk of the double spruce is perfectly straight and reg- 
ularly tapering from the ground to the top. The bark is smooth, 
covered with thin, narrow scales, which on old trunks become 
roundish. On the smaller branches and upper part of the 
trunk, these scales are downward contimuations of the leaves, 
and often come off with them. They are grayish in the mid- 
dle, edged with brown. 
The branches are in whorls of four or more, but, except on 
small trees, the whorls are not very distinct, in consequence of 
the premature decay of two or more of the branches, and of the 
fact that between the whorls are occasionally scattered single 
limbs. When a tree stands by itself, in a sheltered situation 
favorable to its growth, the stages or whorls are regularly dis- 
posed, and, diminishing gradually in length from the ground to 
the top, form a conical head of strikingly regular and symmet- 
rical proportions. ‘To the unpractised eye, this mathematical 
exactness of shape is beautiful, and the spruce is a favorite 
tree and is often placed in the near vicmity of houses. But to 
one studious of variety and picturesque effect, the regular cone 
becomes stiff and monotonous, and the unvarying dark green 
of the foliage has a sombre and melancholy aspect. 
The recent shoots are pretty large, covered with a light 
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