The Republican. [volume] (Oakland, Md.) 1877-current, 1888-05-05
ANIMALS AND SOIL.
The Wonderful and Useful Work
Done by Ants.
What Is Accomplished by Crayfish, Field
Mice, Bugs, Etc.-But the Ants, in Many
Districts, Are the Most Impor-
taut Agents.

The admirable studies of Mr. Darwin
en- the influences of the earth-worms
upon the soil has made it clear that
these animals exercise most impor-
tant effect in its preparation for the use
of plants. Mr.. Darwin's luminous es-
say has served TO call attention to the
effect of organic life on the develop
ment of the soil-coating. In the fol-
lowing pages propose to submit the
results of some studies of general ma
ture, which serve to show that num-
Der of other animals have a consider
able influence on the preparation of
soils.
Our soils, as is well known, depend
upon variety of actions which serve
to break up the rocky matter of the
earth and to commingle that matter
with organic materials more rapidly
than the erosive agents can remove the
detritus from the point at or near
which it decays. For the formation of
the soil two actions at least cre essen
tial. First, the bedrock must DC broken
into fragments sufficiently separated
from each other to permit the passage
of roots between them; second, the
rock fragments must be still further
comminuted and commingled with
organic waste to make the combination
of organic and inorganic matter on
which the utility of the soil absolutely
depends. Although the earth-worms
are undoubtedly very important agents
in overturnng and breaking up of soil,
it appears to me that they are most eff
fective in the titled fields or in the natu-
raj and artificial grass-lands. So far
as l have been able to observe, these
creatures are rarely found in our ordi-
nary forests where thick layer of
leaf-mold, commingled with branches,
lies upon the earth. The character of
this deposit is such that the creatures
are not competent to make their way
through it.. and they therefore in the
main avoid such situations. Moreover,
wherever the soil is of very sandy
nature. earth-worms are scantly found
if they are present at all. These worms
are practically limited to the soils of u
somewhat clayey character, which
have no coating of decayed vegetation
upon them.
AS the greater portion of the existing
soil has been produced in forest regions,
l shall first examine the action of vari-
Gus animals upon the soils of wooded
countries. The mammals are, of all our
vertebrates, the most effective in their
action upon the soil of forests. Twenty
species, or more, of our American man.
mails are borrowers in the forest bed.
They either make their habtations be-
meath the ground or resort TO it in the
pursuit of food. OF these our burrow-
ing rodents are perhaps the most effect
i've, but large number of other small
mammals resort TO the earth and maks
considerable excavations. In forming
their burrows, or in the pursuit of other
burrowing animals, these creatures
often penetrate through the whole or
greater portion of the soil-covering
The material which is withdrawn from
the burrow is accumulated about its
mouth. The result is the overturning
of considerable amount of the earth
and II consequent commingling of the
material with vegetable matter. When
brought to the surface and left exposed
to the action of frost the breaking up OF
the material is greatly favored, and
thus the formation of the soil is facili-
tated.
Considerable as is the effect of bur-
rowing mammals, the principal over,
turning of the earth in our primeva
forests is accomplished by the inverte,
brate animals. Where the woods are
not very dense. and particularly where
the soil is somewhat sandy, our larges
species of ants are very effective agents
in working over the soil Their bur.
rows extend to the depth OF some feet
below the surface, and each hill bring:
to the air several cubic feet of excavatcd
matter, which, as slight inspection
shows, is much c0mmingled with vege-
table matter. Wherever these ant-hills
abound they commonly exist to the
number of score or more on each
acre, and the occupants of each hill, in
many cases, bring as much as a cubic
foot of matter to the surface in the