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

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FOREST TREES OF THE PACIFIC SLOPE.
attached to the tree. Seeds dark brown with areas of yellow-brown. An
unusually large number of seed leaves are developed by seedlings, from 12 to
14 being the usual number. Wood, pale reddish-brown, soft, very brittle, and
wide-grained. This tree is of such rare and limited occurrence that the wood is
of no commercial importance.
LoNG.EvITY.-Little is known of the longevity of this pine, which is rarely
cut. Trees from 10 to 12 inches in diameter are from 75 to 80 years old.
It appears to be a comparatively short-lived pine; its ordinary age is probably
from 100 to 150, and not more than 200 years.
RANGE.
Confined to a limited area in San Diego County and to Santa Rosa Island, southern
California. On the mainland it orcurs in a strip about 1 mile wide on both sides of
the mouth of Soledad River, from a point on the north 3 miles north of Del Mar, a
mile and a half from the Pacific Coast, to a point 5 miles south of Point Pinos.
OCCURRENCE.
Highlands adjacent to sea and on sides of deep ravines and washes leading to coast.
On mainland growing in a disintegrating yellowish sand rock. On Santa Rosa Island,
in a soil of mingled earth and loose rock, or sometimes in rather thick soil over un
broken rock. Largest trees on sheltered sides of hills and spurs of canyons protected
from sea winds; sprawling and distorted in exposed situations. Much scattered and
with little or no other growth except thin chaparral.
CLIMATIC COxnDITIONs.-The temperature of its range varies annually between 25' and
95' F. About 15 inches of rain falls during the year. The air is humid and a large
proportion of the days are cloudy or foggy.
TOLERANCE-Apparently demanding full light, as shown by scanty foliage and growth
in very open, scattering stands. Little is known of its silvical characteristics.
REPrmODUCTiox..-Prolific, annual seeder, bearing well when from 12 to 18 years old.
Seeds discharged mostly during third year, the cones with remaining seeds falling about
the fourth year. Germination takes place in crevices and washed mineral soil. Seedlings
are rather numerous in vicinity of trees, both on mainland and on Santa Rosa
Island.
YELLOW PINES.
Western Yellow Pine.
Pinus puondecrosa Lawson.
DISTINGUISIIING CHARACTERISTICS.
This is a massive, straight-truniked tree with a long, narrow, open crown of
hugely developed bent branches. The narrow columnar crown, with scattered
branches, upturned at their ends, is characteristic. Often one or two large
lower branches are separated from the crown by 20 or more feet of clear
trunk. Trees grown in an open stand bear branches close to the ground, retaining
this long low crown throughout life. The trunk is smoothly cylindrical,
with little taper until the large crown branches are reached. Height, from 125
to 140 feet, with a practically clear trunk of from 40 to 60 feet; diameter, from
3 to 4 feet. Its majestic size is surpassed among its kind only by the sugar
pine. Unusually large trees are from 150 to 180 feet high, while trees are said
to have been found over 200 feet high. The largest diameter recorded is about
5 feet. The bark of old trunks is marked by very broad, shield-like, russet-red
plates, which may be from 3 to 4 inches thick, especially near the base of the
tree. The surface of this bark is peculiar in being made up of small, concave
scales. Younger trees, up to 2 feet in diameter, are quite unlike older ones in
having dark red-brown or blackish. narrowly furrowed bark. Young shoots,
which have a strong odor of orange when broken, are yellowish green and