ere are eighteen recognized species of spruce. The Norway spruce has been chosen as a type for this group because it is so commonly planted in the northeastern part of the United States.
The hemlock is represented by seven species, confined to temperate North America, Japan, and Central and Western China.
[Illustration: FIG. 7.--The Norway Spruce.]
How to tell them from each other: The needles and branches of the spruce are coarse; those of the hemlock are flat and graceful. The individual leaves of the spruce, Fig. 9, are four-sided and green or blue on the under side, while those of the hemlock, Fig. 10, are flat and are marked by two white lines on the under side.
THE NORWAY SPRUCE (Picea excelsa)
Distinguishing characters: The characteristic appearance of the full-grown tree is due to the *drooping branchlets* carried on *main branches which bend upward* (Fig. 7).
Leaf: The leaves are dark green in color and are arranged spi