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

78 FOREST TREES OF THE PACIFIC SLOPE.
central column. They never fall away until the cone is rotted to pieces. Two
seeds are borne under each cone scale. The seeds are light and are provided at
one end with a thin wing which enables the wind to disseminate them widely.
Seed-leaves, sometimes 4, but commonly from 5 to about 15.
The spruces are exceedingly important forest trees. They yield superior
saw-timber and the even-grained wood can be used for a great many purposes.
For paper pulp the wood of these trees is unsurpassed by any other. Seven
species are indigenous to North America, all of which are abundantly, or
exclusively, represented in the LTnited States. Four are distributed over the
western half of the United States, and three range mainly through northeastern
United States and Canada, while two of these extend, almost entirely
in Canada from the Great Lake region, into Alaska.
Engelmann Spruce.
Picea engelmanni Engelmann.a
DISTINGUISHING CIIARACTFRISTICS.
In dense stands Engelmann spruce has a straight, clean trunk with a close,
very short, narrowly pyramidal crown of small branches; the upper part of the
crown has exceedingly short sprays, forming a narrow spire. Such trees are
from 80 to 100 feet or more in height, and from 18 to 36 inches in diameter.
Larger trees occur sometimes. Singly, or in an open stand, it forms a similar
but longer crown, with drooping lower branches which may extend down to the
ground. Such trees are usually from 60 to 80 feet high with very tapering
trunks, and if exposed to heavy winds, the lower branches are often long and
stout. From all of the main horizontal branches hang numerous tassel-like
side branchlets which give the tree a very compact appearance. At high altitudes
it is often not more than 2 or 4 feet high. A spike-like stem bears a few short
densely-leaved branchlets while enormously long branches spread over the
ground from the base of the trunk. The foliage is a deep blue-green, on some
trees with a decidedly silvery or whitish tinge. This silvery tinge is very
marked on young trees; occasionally, however, large and moderately old trees
still retain it. The bark becomes scaly even on rather young trees. On
maturer trunks it is thin, dark purplish-brown or russet-red, and outwardly
composed of very loosely attached small scales. The 4-angled leaves (fig. 29)
are soft to the touch, usually about an inch in length, but often longer, and are
spreading on young branchlets (fig. 29) which-do not bear cones, while on conebearing
twigs they are commonly crowded and of a shorter type; they are often
crowded and curved so as to appear mainly on the upper part of the branchlet.
The point of the leaf is characteristically short and flat; short leaves exhibit
this more strongly than do the longQr ones. A cross-section of the leaf shows no
resin ducts. A disagreeable odor is emitted by leaves and young shoots when
crushed. Young shoots are more or less minutely hairy and may remain so for
about three years. The cones, which mature in a single season, are ripe by the
middle or latter part of August. Most of them are borne near the top of the
crown. By October the seed is usually all shed. Cones (fig. 29) vary greatly
a Dr. George Engelmann did not name this tree in honor of himself. Parry (Trans.
Acad. Sdi. St. Louis, II, 122, 1863) recognizing that the tree had been referred by Engelmann
to Abies nigra (another species), called it Abies Engelmanni, which proved to be a
nomcn nudum. Later Engelmann (loc. cit., 212) cited Parry's name, and In doing this
formed a new name, Piecea engelmasni, which he credited to Parry. As a matter of fact,
Parry did not write Picea engelmanni, consequently Engelmann was the first publisher of
Picea engelmanni, but certainly not with a knowledge that he must be cited as Its author.