Imagine a stranger who has lived all his life in a desert where no trees
grow, coming suddenly into our village, and looking with wonder at the
trees that shade the streets. He knows only the spiny cactuses, and other
plants of the desert. His first question would be, “What are these great
plants that stand so tall?” The name, _tree_, is new to him. It would be
a strange experience to take such an eager and ignorant man and show him
the trees, on the streets, planted in orchards, and growing wild in the
woods outside of the town. His questions set us to thinking. He wants to
know why we plant trees, and how we use those that grow in forests.
First, we tell him the uses of the living trees. Up and down the streets
they are set for shade, and for their beauty. Rows of evergreens set
close together make a protecting wall of green against the cold winds.
Low clipped hedges of many kinds of trees make living boundaries, much
more beautiful than wooden or wire fences. On lawns and near houses trees
are planted for their beauty and for their shade. Orchards of fruit trees
are planted because they furnish food. Nut orchards are set out for the
same reasons.
The trees cut down in the woods, and sawed at the mills give us lumber to
build houses to live in, and furniture to make them comfortable, and the
same forest furnishes the fuel that keeps us warm. There is so much to
explain to a person who discovers trees for the first time. It takes a
long time to tell all we know.
Do we think that we know a great deal about the uses of trees? If so, we
are mistaken. The truth is that trees serve us in ways of which we have
never dreamed.
We must travel over the world and read a great deal to learn how the
people of other countries make use of trees. The basswood or linden which
nobody cared to use except for fuel in the Middle West might pass for a
useless tree, compared with those whose wood is harder and stronger. But
in older countries people have quite a different opinion of the tree.
In Russia the tough bark of young lindens is used to make the shoes of
peasants. Ropes, fishing nets, and braided mats are made from the same
tough “bast” fibres, which are very long and tough in this family of
trees. The seeds yield oil that is declared to be quite as good as olive
oil for cooking, and for the table. Perfume is distilled from the
flowers. Cattle browse on the twigs and leaves. The wood is the carver’s
delight—soft, white, free from knots and imperfections. It is used for
bureau drawers, carriage bodies, shoe soles, barrel staves and paper
pulp. Its twigs make artist’s charcoal pencils.
Linden trees are planted for shade in many countries, and in Europe they
are often cut into grotesque shapes of animals as they grow. They are
clipped into hedges, as close as box or yew. In America they are usually
allowed to grow naturally, as shade trees. European species are rather
more symmetrical than our native kinds.
The Indians of the Northwest used the soft inner bark of the tamarack
pine for food. They cut down the trees, strip them of bark, and scraped
out this soft lining layer. With water, they mash it into a pulp, which
they cook and then mould into large cakes. A hole is next dug in the
ground, lined with stones, and a fire is built in it. When the stones are
hot, all ashes are removed, and the cakes, wrapped in green skunk cabbage
leaves, are laid in. A fire of damp moss is built on top, and thus the
cakes are thoroughly, baked. To insure their keeping, they are next
smoked in a close tent for a week or more. This dries and cures them so
that they may be safely packed away for future use. These hard, dry cakes
are afterward broken into pieces and boiled. When the mass softens and
cools, it is ready to eat. The fat of different animals is used for
butter on this strange Alaskan bread.
[Illustration: Flowers and fruit of the wild black cherry]
[Illustration: The delicate white flower clusters of the serviceberry
tree]
Everybody knows that trees bear fruits of many kinds that are useful as
food for men and beasts. Spices, such as nutmegs, mace, cloves, and
allspice, may be added to this list of fruits which we have as human
foods.
The bark of birches is invaluable to the Indians for the making of their
canoes, baskets, and all kinds of utensils. Huts and teepees are walled
with it. Rope and coarse cloth are made out of the fibre of mulberry
bark, and berry baskets out of the bark of the lodgepole pine. The
fibrous roots of the larch tree furnished tough thread, with which the
Indians sewed canoes of birch, and they made them water-tight with the
gum of the balsam. The brown gum that oozes from wounds of the Western
larch is sweet and starchy. The Indians discovered in it a valuable
article of food.
One of the latest uses of wood is the making of paper, although the white
hornet showed in its conical paper nest that this could be done. She has
been making wooden paper for hundreds of years, scraping the wood from
the surface of weathern-worn fence boards, and from the dead limbs of
forest trees. Our newspapers are made of ground wood, cooked to a soft
pulp, and rolled out into thin sheets. The high price of paper makes it
worth while to gather up papers, bleach them, convert them into pulp, and
roll them out again into sheets. Spruce wood and poplar are among the
cheap woods which have come into demand at the paper mills. The forests
of these trees, counted of little use for lumber, have become valuable
because the paper mills can use them.
Look about the room, and a dozen articles, beside the chairs and table,
are products of wood, or in some way owe a debt to trees. The paint that
covers the window sash and frames was mixed with turpentine, which is
obtained from the pitchy sap of pine trees. The shades and curtains are
coloured. Dyes of many kinds are extracted from the various dyewoods,
trees that grow in tropical forests. The newspaper and the books on the
shelves are made of wood pulp. The lacquered box from Japan is a handsome
thing. The lacquer varnish is the sap of a certain Oriental sumach tree.
The perfume of the gloves in the box is made from the fragrant gum of an
Oriental sweet gum tree. The skin out of which the gloves were made was
tanned, not with bark, but with the acorn cups, or galls, of a European
oak.
The shoes on your feet are made of leather. The hemlock trees that grow
on the hills were stripped of their bark by peelers in early spring.
Black oak and chestnut oak are also stripped in our woods. Carloads of
bark are shipped to the tanneries to be used in the tanning of skins
which changes them into leather.
That beautiful book upon the table is bound in Russia leather. The acorn
cups of a European oak were used to tan the skins that made this leather
so much more beautiful than that of your shoes. Your gloves are made of
kid skins tanned in Europe. For this particular work the nut-like galls
that grow on certain oak trees are gathered in the woods.
Tannin is the substance in oak bark which makes it valuable in tanning
leather. A high percentage of tannin is found in oak galls. For this
reason they are gathered in many countries, and are among the most
valuable and high-priced supplies for the establishments that tan skins
for gloves. The most expensive inks and dyes, those that do not fade, but
are practically permanent, are made from selected oak galls.
Oak apples are a strange fruit, found in more or less abundance on the
leaves of our own oak trees in autumn. You have seen them in summer time,
plump, green balls, sometimes as large as a hen’s egg, but globular,
sitting upon a leaf. In autumn the balls take on the colour of the dying
leaves.
The same tree may have hard little marble-like balls growing on its
twigs. These are of different sizes, and it is not unusual to find a hole
in the side of each.
All such outgrowths on the leaves and twigs of oaks are called galls, and
they are chiefly caused by winged insects called gall-gnats. An egg is
laid in early spring, in a slit pierced in the twig or leaf. As this egg
hatches, the tissue about it is disturbed in its growth by the presence
of this feeding grub. The soft leaf pulp, or the tender tissues of the
twig that surround it, are exactly what the grub likes to eat. Food and
drink are all about it, and as it feeds, it grows. The leaf swells, and
so surrounds the grub with an abnormal growth. The grub still feeds, and
the swelling becomes larger, until finally, when the insect ceases to
eat, it is housed in the peculiar ball which we know as an oak gall. Each
species of gall-maker is known by its house.
The oak apples are of several kinds. Some are empty except for a little
shell in the centre, in which the fat grub sleeps. Sometimes the
substance within the “apple” is corky, sometimes spongy. Bullet galls,
which form on twigs like little marbles, are usually solid to the centre,
where the grub lies until the time comes for it to bore its way out to
the surface, and fly away, to lay eggs which will produce other galls.
Usually oak galls, found in winter, contain the sleeping grub, whose
transformation into a winged insect waits until the coming of spring.
The cork in your ink bottle is the bark of an oak tree. Go to Portugal or
to Northern Africa, and you may see the cork harvest in progress in July
or August. There is no place to go for genuine cork except to a small
evergreen oak that rarely reaches a height over thirty feet. When these
trees are twenty-five years old, a hard, thin layer of bark is stripped
off. This is a valuable tan bark, but it is not in the least corky. The
tree now produces a spongy bark entirely different from the first. It is
not disturbed for eight or ten years. This is stripped off. It is the
poor quality of bark which fishermen use to float their nets with.
Ten years later the bark is stripped again. It is better in quality than
the first. Each ten years brings the bark stripper again to the tree. In
the fiftieth year, the bark is of the finest quality, and for fifty years
that follow there are five strippings of bark of the highest grade. Then
the quality becomes poorer. The trees are cut down, the bark is sold to
the tanners, and the wood is used for charcoal or for fuel.
It is a very particular job to get the cork off and leave the under layer
uninjured. The trunk is stripped from the ground to the point where it
branches, and the inner “mother bark” must not be bruised, for no more
cork will grow on any bruised spot. Two circular cuts are made, one at
the top, one at the bottom of the columnar trunk, then two opposite slits
are made dividing the bark of the trunk into two halves. These curved
plates are worked off by inserting a wedged-shaped tool between the bark
and the trunk, and gradually working it further in until the whole curved
plate of cork comes off. These two big sheets are steamed and flattened,
then bound in bundles, and shipped to wholesale dealers in cork.
The owner of a grove of cork oaks must wait ten years between crops of
the bark, but every year three crops of acorns are borne on these trees.
The pigs of the owner, turned into the grove, fatten on this rich food.
So the little trees are very profitable in two ways.
In the south of Europe, the handsome, evergreen holm oak grows wild; its
glossy leaves and compact form remind us of our holly trees. It is one of
the most valuable ornamental oaks, but as a fruit tree, it has unusual
value. Its acorns are sweet and rich, and the crop is heavy. Hogs are
fattened upon them. In earlier days they were used as human food, and
even now gipsies gather them to eat. Its acorn cups, bark, and the galls
it bears are of the very best quality. They are used in the most
particular jobs of dyeing and tanning.
Under ground, the holm oak bears a strange fruit—a fungus called
“truffle” develops on the roots. These truffles are somewhat like
mushrooms in their growth. They are far more delicious to eat, and
expensive to buy than ordinary mushrooms. The best of them are found in
France, and French people are especially fond of them.
Trees that grow on chalky lands are more likely to produce truffles. At a
dozen years old, they begin to yield, and truffles may be found upon
their roots for about twenty-five years.
Not every holm oak has truffles on its roots. The finding of these
delicacies is a very interesting and exciting game, and a great deal of a
lottery. There is but one way to find them, and that is by the sense of
smell. The truffle has a rich, strong odour. Dogs and pigs are the only
animals that are able to find it. The truffle-hunter is usually an old
woman, who goes with a trained pig or a trained dog into the oak forest.
She has a basket, and a spading fork, and she keeps a close eye on her
four-footed partner. If the pig, in rooting about under an oak, suddenly
becomes excited, and begins to root furiously, she drives him away, and
digs out the precious ball of fungus he has scented. It is irregular in
form, and looks somewhat like a potato. Meanwhile the pig locates
another, and is again disappointed. The truffle dog is treated in the
same manner. Unless put into a pen, or chained at night, these
truffle-hunters are likely to take to the woods and feast when no one is
by to interfere with their pleasure.
Truffles are shipped in cans to the United States, but we have not yet
discovered them growing on the roots of our oak trees. Probably we have
not yet looked for them with sufficient care and patience.