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

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FOREST TREES OF THE PACIFIC SLOPE.
teristic is their ability to grow readily from root or branch cuttings and to sprout
vigorously and persistently from cut stumps of almost any age.
SALIX. WILLOWS.
The many trees (and shrubs) of the willow group are at once distinguished
by the quinine-like bitter taste of their bark, which is harmless. Their deciduous
leaves, variable in form, are most frequently long and narrowly pointed,
smooth throughout, or coated with fine silky hairs on their under surfaces;
their margins may be entire (uncut) or variously toothed. They grow singly
on the branches at points alternating with each other on different sides of the
branches (never in pairs, one opposite the other on two sides of the branch).
Willow leaves are peculiar in having a pair of ear-shaped, minute or large, leaflike
growths at the base of their stems. These are larger and therefore more
conspicuous on vigorous annual shoots, on which they may remain until they
fall with the leaves, while on other stems they are present only during the
early growth of the leaves. The leaves may fall in the autumn without much
change of color, or they may first turn a lemon yellow. Leaf-scars (left by the
falling leaves) are marked by three minute dots (fibro-vascular bundles severed
by the parting of the leaf stem). The fruit and seed are sufficiently described
under the family (Salicacea-).
Annual sprouts of willows are exceedingly strong and withy, while older
branches from the crown are often peculiarly frangible; twigs are notably
frangible where they join a larger branch or fork. A frequent habit of growth
among willows is to produce several trunks from a single greatly extended rootstock,
while some species regularly have single, isolated trunks. Species of the
latter form have been readily admitted to be trees. Those forming clusters of
very large trunks have, on the other hand, been denied this rank for some time,
even though the trunks were otherwise tree-like. For practical purposes, however,
they certainly are trees. A striking and valuable cultural feature of the
willows is their remarkable vitality, which enables them to grow persistently
from cut stumps and easily from pieces of branches or roots. Through this quality
some of the foreign willow trees have been pollarded for centuries, the shoots
being used for coarse baskets and other economic purposes.
The willows are swamp or maoist-ground species, finding their habitat from
sea level to an elevation of 10,000 or more feet.
Willow wood is soft, light, usually brittle but firm, commonly pale brown,
tinged with red; the heartwood of some species is very durable when exposed
to water or earth. It has various minor economic uses, especially for cricket
and ball bats and for gunpowder and charcoal. The greatest commercial usefulness
of willows appears to have come mainly through the manufacture of
baskets and furniture from shoots or rods produced in one season. Some of
the tree willows produce moderately large, clear trunks, which would yield
lumber, but as a rule their boles are of poor form for saw timber.- Except in
generally forestless regions, where willows and their allies, the cottonwoods,
become useful because no other trees are available, these trees have little to
commend them in comparison with many other trees of demonstrated value.
They are, however, distinctly important to the forester for binding shifting
sands and for holding banks of streams in soft bottoms where serious ruin of
agricultural lands may result from the erosion of unprotected banks.
Tree willows attain their mature growth in comparatively few years-50 to
150 years-after which the trunks become hollow, may gradually show signs
of decay, and are easily broken by storm. Their tenacious vitality, however,
permits them to grow for centuries, repairing or replacing broken trunks by
new stem or root sprouts.