The Virginia enterprise. [volume] (Virginia, St. Louis County, Minn.) 1893-19??, 1905-03-31
GROWTH O. I OR ESTS.
CERTAIN KINDS OF TREES ONLY
. THRIVE IN SOME PLACES.
Singular Provision Of Nature in Pro-
~ lection Of Some species-Im-
portant Factors in Repro < @
.r'. duction. 49,

The laws which govern the distribu-
ton of trees produce the two great types,
the pure and the mixed forest. Thefor-
mer is the result of local conditions
which trees of one kind can only sur
vive.
In the north woods the balsam occu-
pies the swamps, usually to the exclu-
sion 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 de-
mands of the bull pine upon moisture
enable it to form pure woods on soil
too dry to support other native 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 is found the mixed for
est, the number OF species in mixture
depending upon the suitability of the
locality to forest growth.
Upon the hardwood flats of the AdirOn-
dacks the hard maple the yellow birch
and the beech are the only deciduous
trees able to withstand the severe CHI
mate. In the southern Appalachian for
eSts. where the trees of the north and
south meet under conditions favorable
to both, more than 100 different kinds are
found.
The distribution of trees, therefore, is
the joint result of local conditions and
of the individual and varying require
ments of the different species upon mois-
| ture, soil and climate. The laws, how
ever, which govern forest distribution
are not identical with those which reg
ulate the behavior of trees in mixture.
if undisturbed, maintains the same pro-
portion in the mixed forest. Why does
not the hard maple drive out it's COM
! petitors 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?
| is an unrelenting struggle going on. 1t
is Interesting to inquire how the COM
batants are armed and why the repre-
sentation of each species remains un-
changed.
The more important of the character
istics which affect the capacity of tree
! to hold it's own in mixture with trees of
| other kinds are it's demands upon light,
it's rate of growth and it's power of re-
! production. No two species require an
equal amount of light, grow at the same
rate or are Identical in their capacity to
reproduce themselves.
The endowments of each with habits
differing from those of it's neighbors,
| but with strength and weakness so bal
anced 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 it's ability to endure dense
| shade. has been given the power to hold
| it's own against faster growing COM
petitors, some of which exceed it greatly
in their capacity to reproduce them
| selves. The young spruces which spring
up mere ana there throughout the forest
struggle along under the heavy crowns
of the hard woods where tree making
more insistent demands upon light could
not thrive
In the forests of the southern Appa-
lachians the oak is in many localities
the characteristic tree. Growing rapid
ly and exceedingly hardy, it might be ex-
| pected to increase steadily it's proper
ton of the mixture The equilibrium is
| maintained through the fact that the oak
can endure but little shade and that it's
seed is heavy. limiting it's reproduction
to the immediate vicinity of the parent
tree
Cause of Japan's Success.