Draining The Soil
Categories:
THE SOIL
A wise man was once asked, "What is the most valuable improvement ever
made in agriculture?" He answered, "Drainage." Often soils unfit for
crop-production because they contain too much water are by drainage
rendered the most valuable of farming lands.
Drainage benefits land in the following ways:
1. It deepens the subsoil by removing unnecessary water from the spaces
between the soil partic
es. This admits air. Then the oxygen which is in
the air, by aiding decay, prepares plant food for vegetation.
2. It makes the surface soil, or topsoil, deeper. It stands to reason
that the deeper the soil the more plant food becomes available for plant
use.
3. It improves the texture of the soil. Wet soil is sticky. Drainage
makes this sticky soil crumble and fall apart.
4. It prevents washing.
5. It increases the porosity of soils and permits roots to go deeper
into the soil for food and moisture.
6. It increases the warmth of the soil.
7. It permits earlier working in spring and after rains.
8. It favors the growth of germs which change the unavailable nitrogen
of the soil into nitrates; that is, into the form of nitrogen most
useful to plants.
9. It enables plants to resist drought better because the roots go into
the ground deeper early in the season.
A soil that is hard and wet will not grow good crops. The
nitrogen-gathering crops will store the greatest quantity of nitrogen in
the soil when the soil is open to the free circulation of the air.
These valuable crops cannot do this when the soil is wet and cold.
Sandy soils with sandy subsoils do not often need drainage; such soils
are naturally drained. With clay soils it is different. It is very
important to remove the stagnant water in them and to let the air in.
When land has been properly drained the other steps in improvement are
easily taken. After soil has been dried and mellowed by proper drainage,
then commercial fertilizers, barnyard manure, cowpeas, and clover can
most readily do their great work of improving the texture of the soil
and of making it fitter for plant growth.
=Tile Drains.= Tile drains are the best and cheapest that can be used.
It would not be too strong to say that draining by tiles is the most
perfect drainage. Thousands of practical tests in this country have
proved the superiority of tile draining for the following reasons:
1. Good tile drains properly laid last for years and do not fill up.
2. They furnish the cheapest possible means of removing too much water
from the soil.
3. They are out of reach of all cultivating tools.
4. Surface water in filtering through the tiles leaves its nutritious
elements for plant growth.
=EXPERIMENTS=
=To show the Effect of Drainage.= Take two tomato cans and fill
both with the same kind of soil. Punch several holes in the bottom
of one to drain the soil above and to admit air circulation. Leave
the other unpunctured. Plant seeds of any kind in both cans and
keep in a warm place. Add every third day equal quantities of
water. Let seeds grow in both cans and observe the difference in
growth for two or three weeks.
=To show the Effect of Air in Soils.= Take two tomato cans; fill
one with soil that is loose and warm, and the other with wet clay
or muck from a swampy field. Plant a few seeds of the same kind in
each and observe how much better the dry, warm, open soil is for
growing farm crops.