Yorkville enquirer. [volume] (Yorkville, S.C.) 1855-2006, 1904-11-22
Misetllansuas 8sading.
HOW FORESTS GROW.

HOW FORESTS GROW.
Thsrs Are Two Great Types, the Pure
and Mixed.
The laws which govern the distribu-
ton Of trees produce the two great
types, the pure and the mixed forest.
The former is the result Of local con-
ditions which trees of one kind only
can survive.
In the north woods the balsam oc-
cupies the swamps, usually to the ex-
clusion Of all competitors, since no
other of the native trees can thrive
In wet places. In the Black Hills and
other parts of the middle west the
small demands Of the bull pine upon
moisture enable it to form pure woods
on a soil too dry to support other ma
tive trees. The jack pine Of the New
Jersey barrens and the long leaf pine
Of the southern states grow IN pure
or nearly pure stands since they alone
can withstand the peculiar conditions
of these regions.
Where climate and soil are favorable
to various trees we find the mixed
forests the number Of species In mix
ture depending upon the suitability Of
the locality to forest growth.
Upon the hardwood flats Of. the
a Lar -
low birch and the beech are the only
deciduous trees able to Withstand the
severe climate. In the southern Appa-
.lachian forests, where the trees Of the
north and south meet under conditions
favorable to both, we find more than
100 different kinds.
The distribution Of trees, therefore,
is the joint result Of local conditions
and Of the individual and varying re-
quirements of the different species up
on moisture, soil and climate. The
laws, however, which govern forest
distribution are not identical with
those which regulate the behavior Of
trees in mixture. They do not ex-
plain why each species, IL undisturbed,
maintains the same proportion In the
mixed forest. Why does not the hard
maple drive out its competitors In
the Adirondacks, the oak gain the
upper hand in the forests Of the
southern Appalachians, the red fir ex-
terminate the western hemlock on the
Pacific slope?
Wherever a mixed forest occurs
there is an unrelenting struggle going
on. Let us see how the combatants
are armed and why the representation
Of each species remains unchanged.
The more important Of the charac-
teristics which affect the capacity Of
tree to hold its own in mixture with
trees Of other kinds are its demands
upon light, its rate Of growth and its
power of reproduction. No two spe-
cies require an equal amount Of light,
grow at the same rate or are identi-
cal in their capacity to reproduce
themselves. The endowment Of each,
with habits differing from those Of its
neighbors, but with strength and
weakness so balanced that all which
occur in mixture enter the struggle for
existence upon an equal footing, Is one
Of the marvellous feats Of nature.
The red spruce Of the North woods,
through its ability to endure dense
shade, has been given the power to
hold it's own against faster growing
competitors, some Of which exceed 1t
greatly in their capacity to reproduce
themselves. The young spruces which
spring up here and there throughout
the forest struggle along under the
heavy crowns Of the hard woods, where
a tree making more insistent demands
upon light could not survive.
In the forests Of the southern APP
palachians the oak is in many locali-
ties the characteristic tree. Growing
rapidly and exceedingly hardy, it might
be expected to increase steadily its
proportion in the mixture. The equi-
librium Is maintained through the fact
that the oak can endure but little
shade and that its seed is heavy. linn
iting its reproduction to the immediate
vicinity Of the parent tree.
In the same region the yellow poplar
and the chestnut, both trees which
grow rapidly and are capable Of en-
during considerable shade, are con-
trolled, the one because much Of Its
seed is barren, the other because many
Of the nuts are eaten by animals. And
the red cedar, Of slow growth and
sparse representation, is aided through
the distribution of its seeds by birds,
with their power to germinate unim-
paired.
The aspen, short lived and requiring
much light, holds its own with longer
lived and shade enduring trees be-
cause its downy seed is produced In
great quantities and is scattered far
and wide by the wind. The ash and
the Eastwood, Of rapid growth and
bearing an abundance Of seed, are
withheld by strong demands upon
light and by the seed Of a fresh and
fertile soil. The red fir, equaled by
few North American trees in rapidity
of growth and otherwise well equip
ped to gain the upper hand IN ne re,
gion, Is controlled through the usNal
failure of its seed to germinate excepi
when accident has removed the leaf
litter and exposed the mineral soil.
The study Of trees as living, striving
organisms in a world OF their own
the forest. Every day spent In the
woods will be pleasanter for some In
sight gained into what Is going on
within il. and an earnest observer can
gain knowledge Of practical value by
an attempt to discover the Il factors tross
which control the occurrence OF trees
IN roixture. Forestry, which deals with
the development Of the highest utility
of forests means a thorough under
standing Of the habits Of treesiN(tRer-
ton w. Price in Youths C2X ~