The First Book of Farming | Page 8

growth. Now, if we can get a cultivator, we will have that run along the
row and then wash away the loosened soil. It will be found that few, if
any, of the main lateral roots have been injured.
Is it of any value to the farmer to know that roots extend laterally three
to six feet and more on all sides of the plant, and that every part of the
upper soil is filled with their branches and rootlets? This fact has a
bearing on the application of manures and fertilizers. It tells the farmer
that when he applies the manure and fertilizers to the soil he should
mix the most of them thoroughly all through the soil, placing only a
little directly in the row to start the young plant.
To find out how quickly the roots reach out into the soil, wash the soil
away from some seedlings that have been growing only a few days, say,
seven, ten and fifteen. (See Fig. 11.)
From our observations, then, we have learned the important lessons of
deep, thorough plowing, careful shallow after-cultivation, and that
fertilizers should be well mixed with the soil.

We are now ready to go back to our study of the habit of growth of
roots, and can perhaps tell something of how the root does its work for
the plant.
It is very easy to see how the roots hold the plant firmly in place, for
they penetrate so thoroughly every part of the soil, and to such
distances, that they hold with a grip that makes it impossible to remove
the plant from the soil without tearing it free from the roots.
It is also on account of this very thorough reaching out through the soil
that the roots are able to supply the plant with sufficient moisture and
food.
We have doubtless observed that most of these roots are very slender
and many very delicate. How did they manage to reach out into the soil
so far from the plant? Or where does the root grow in length? To
answer this question I will ask you to perform the following
experiment:
=Experiment.=--Place some kernels of corn or other large seeds on a
plate between the folds of a piece of wet cloth. Cover with a pane of
glass or another plate. Keep the cloth moist till the seeds sprout and the
young plants have roots two or three inches long. Now have at hand a
plate, two pieces of glass, 4 by 6 inches, a piece of white cloth about 4
by 8 inches, a spool of dark thread, and two burnt matches, or small
slivers of wood. A shallow tin pan may be used in place of the plate.
Lay one pane of glass on the plate, letting one end rest in the bottom of
the plate and the other on the opposite edge of the plate. At one end of
the piece of cloth cut two slits on opposite sides about an inch down
from the end and reaching nearly to the middle. Wet the cloth and
spread it on the glass. Take one of the sprouted seeds, lay it on the cloth,
tie pieces of thread around the main root at intervals of one-quarter inch
from tip to seed. Tie carefully, so that the root will not be injured. Place
the second pane of glass over the roots, letting the edge come just
below the seed, slipping in the slivers of wood to prevent the glass
crushing the roots. Wrap the two flaps of the cloth about the seed. Pour
some water in the plate and leave for development. (Fig. 12.) A day or
two of waiting will show conclusively that the lengthening takes place

at the tip only, or just back of the tip. Is this fact of any value to the
farmer? Yes. The soft tender root tips will force their way through a
mellow soil with greater ease and rapidity than through a hard soil, and
the more rapid the root growth the more rapid the development of the
plant. This teaches us again the lesson of deep, thorough breaking and
pulverizing of the soil before the crop is planted.
We have learned that the roots grow out into the soil in search of
moisture and food, which they absorb for the use of the plant. How
does the root take in moisture and food? Many people think that there
are little mouths at the tips of the roots, and that the food and moisture
are taken in through them. This is not so, for examination with the most
powerful microscopes fails to discover any such mouths. Sprout seeds
of radish, turnip or cabbage, or other seeds, on dark cloth, placed in
plates and kept moist. Notice the