De I. VNER VEW D Forest Trees of the Pacific Slope

FOREST TREES OF THE PACIFIC SLOPE. 181
OCCURRENCE.
On dry exposed mesas, low, dry mountain slopes, and rather moist canyon bottoms
(where best tree form occurs), in dry, rocky, sandy, or gravelly soil, but often very
scanty in the latter sort.
Nothing is known now of its silvical habits in Pacific region, where It is comparatively
rare; but single trees or small groups are commonly scattered among pliion pine,
one-seed juniper, mountain mahogany, and narrow-leaf cottonwood, in Rocky Mountain
range.
CLIMATIC CONDITIONS, TOLERANCE, AND REPRODUCTION.-Not determined. In protected
canyons and other sheltered sites, it appears to endure (in most soils) considerable
shade of broadleaf trees, closely resembling Juniperus virginiana in this respect. Usually
a prolific seeder.
Western Juniper.
Juniperus occidentalis Hooker.
DISTINGUISHING CHARACTERISTICS.
Western juniper, a high mountain tree, is chiefly known simply as "juniper."
Because of its uniformly higher range it is not likely to be confounded with the
California juniper of a much lower zone, which it resembles in general appearance.
Western juniper has a round-topped, open crown, extending to within a
few feet of the ground, and a short, thick, conical trunk. Height, from 15 to 20
or, less commonly, 30 feet; only rarely 60 feet or over; taller trees occur in protected
situations; diameter from 16 to 30 inches, exceptionally from 40 to 60
inches. The trunks, chunky and conical in general form, and with ridges and
grooves, are usually straight, even in the most exposed sites, but are sometimes
bent and twisted. With its stocky form this tree develops enormously long and
large roots which enable it to withstand unharmed the fierce winds common to
its habitat. There is rarely more than from 4 to 8 feet of clear trunk, while
huge lower branches often rise from the base and middle of the trunk like
smaller trunks. Of the other branches, some are large and stiff, standing
out straight or trending upward from the trunk, while many are short ones. Sometimes
the top is divided into two or three thick forks, giving the tree a broader
crown than usual. In such cases, when the trees are growing in flats with deep
soil, the crowns are dense, symmetrical, round-topped, and conical, and extend
down to within 6 feet of the ground. Young trees have straight, sharply tapering
stems and a narrow, open crown of distant, slender, but stiff-looking, long,
upturned branches. Often in old age the branches are less vigorously developed
and droop at the bottom and middle of the crown, but their tips Continue to
turn upward. The bark is a clear, light cinnamon-brown, one-half to 1 inches
thick, distinctly cut by wide, shallow furrows, the long flat ridges being connected
at long intervals by narrower diagonal ridges. It is firm and stringy.
Branchlets which have recently shed their leaves are smooth, and a clear reddish
brown. The bark on them is then very thin, but later on it is divided into
loosely attached, thin scales of lighter red-brown.
The short, pale ashy-green, scale-like leaves (figs. 71, 72) clasp the stiff twigs
closely, the longer, sharper leaves of young, thrifty shoots spreading slightly
only at their points. All leaves are prominently marked on the back by a glandular
pit, whitish with resin. Groups of three leaves clasp the twigs successively,
forming a rounded stem with 6 longitudinal rows of leaves. The leaves
produced each season die in about their second season, after which they are
gradually forced off by the growth of the branehlets. The "berries" (figs. 71,
72), one-fourth to one-third of an inch long, mature about the first of September
of the second year, when they are bluish black, covered with a whitish bloom;