The Roots of a Plant 
IT is the business of the horticulturist or fruit-grower to 
cultivate plants. Each plant is made up of several 
distinct parts, namely, the roots, stem, branches and 
flowers. Is the "rower familiar with the uses of these 
various parts, and does he know the function of each one 
of them? The tree, as contrasted with the vegetable 
plants, differs somewhat in the make-up, but essentially 
all of the parts are similar to each other and all similar 
parts are used for the same purpose. We cannot say that 
any one part of the plant is more important than any 
other, because the plant cannot be considered whole with 
the loss of any part. Since no plant is complete without 
all of its parts, then to have the plant grow, reproduce 
and furnish us with fruit and seed, all parts must work 
together. 
The most singular thing is that the grower can guide 
the natural development of plants to suit his particular 
purpose. He must, however, know how and when to 
make use of the natural processes, and how to guide the 
development in such a way so as to realize the end he has 
in view. In some cases he only cultivates the plant in its 
normal form ; in others he makes the plant more useful 
by increasing its productiveness; in still other cases by 
improving its quality of fruit, etc. 
A plant, then, must not be looked upon as an unchange- 
able organism, nor restricted to any definite form, but as 
a plastic thing which can be changed in all of its parts to 
suit the needs of the grower. This changing the form 
in a plant is only possible when the planter knows the 
different parts of a plant and the needs of each part. 
Every plant has two objects in view, first to reproduce 
itself, and, second, to grow and preserve itself. Each 
part of the plant contributes its share to gain these ends. 
The root holds the plant in the soil and absorbs the plant 
food from it. The stem supports the leaves, flowers and 
fruit, and forms a connecting link between the roots and 
the top. The leaves manufacture the food materials. 
The flowers produce seed which develop into new indi- 
viduals. 
The root represents the direct downward continuation 
of the stem. It supports the plant and holds it in position. 
It absorbs the plant food and makes it possible for the 
plant to increase in size. 
In order to fully understand the value of a root we 
must first know something of its structure. YVe must 
know what it is made of and how it assists the plant. 
Every grower knows that the root does absorb watery 
material, and that the development of this absorbing sur- 
face of a root is proportional to its need for water. The 
question naturally arises as to how the root absorbs this 
water, and what part of the root does it? This all-im- 
portant point is very hazy in the minds of many growers, 
as evidenced by their treatment of plants, when mulching 
and cultivating is practiced. Main- people are of the 
opinion that in order to get food to the plant this food 
must be placed close to the trunk of the tree. This is not 
the case, and food so placed is of little or no value to 
the tree. 
Let us. for convenience, divide the roots of a plant into 
three parts — first, the large main root leading from the 
stem; second, the small, fibrous roots which branch from 
the main root^, and, third, the very small roots which are 
called "root hairs." In addition to the three divisions 
mentioned, we have another very important region in 
every growing root, namely, the "root cap." All roots 
are composed of cells, the same as the rest of the plants, 
and these cells are variously modified to suit special pur- 
poses. The root hairs then are not the root in the sense 
that we think of a root, but a modified cell. It is these 
little root hairs which do all of the work of absorbing the 
plant food. They are the important part in the root 
system of the plant. 
If we examine a root hair we find that it is a slender 
tube filled with liquid. It projects from one of the ex- 
ternal cells of the root. These cells or root hairs form 
the outer layer in certain regions of the root. Root hairs 
are very thin walled, and by elongating, greatly increase 
their absorbing surface. Because of this condition, the 
root hairs present a large absorbing surface in a small 
region. 
Root hairs are only found in definite regions on the 
root, and this region is close to the tip of the small roots, 
just back of the root cap. The)- are not found on the 
larger or older roots. They are continually advancing 
their position, and as the root grows the root hairs die or 
are destroyed, and new ones are continually being formed 
and replacing the old ones. 
When the cells divide and the root grows, it becomes 
necessary for the tender cells to be protected in some 
way, and that is done by the root cap, which is made of 
thicker cells which are continually being destroyed by 
pushing through the soil. As the root cap is destroyed 
it is replaced by new cells, and so continues its growth. 
The roots of the plant vary in their ability to elongate, 
and in some plants we have a small ball of roots com- 
paratively close to the plant, while in others the roots ex- 
tend great distances. The length that the roots will grow 
depends upon the kind of soil, the amount of water and 
plant food available. If the soil is rich and has plenty of 
water present, the roots do not have to reach out great 
distances to get the required amount of food. If the soil 
is poor and the water supply limited, the roots must travel 
long distances to get the required amount of food. In 
either case the absorbing part of the root is near the ends 
of the growing roots and there is the place that the food 
must be supplied if any value is to be derived from it. 
In the treatment of roots we must consider two things: 
first, what part the root plays in relation to the plant, and. 
second, whether it is of economic value in supplying us 
with food. In biennial or perennial plants the roots, in 
addition to absorbing water, are also used as a store- 
house for food, which the plant uses at some future time. 
In some annual plants with tuberous roots, the food ma- 
terial is stored and used by us for food, as in the sweet 
potato. Since the roots are store-houses for food, it is 
important that the proper treatment be given to them 
when transplanting is necessary. 
Since there is a direct relation between the roots and 
the leaves of the plant, and since the leaves draw upon 
this reserve food stored in the roots when the plant can- 
not absorb or make food, it behooves us to aid the plant 
as much as we can when transplanting it. 
When transplanting trees or shrubs the root system is 
always injured. The most apparent injury is the loss of 
the root tips and the root hairs immediately behind them. 
In such a case, by the loss of the part of the root that 
takes up the plant food, it becomes apparent that the 
branches are in greater proportion than the roots, and 
that they will consequently draw too heavily on the stored 
food. How, then, can this root system absorb sufficient 
water for the development of the whole plant, after a 
great part of it has been torn off and all the root hairs 
killed? Even if we watered the roots, we could gain 
nothing, because the small roots containing the root hairs 
have been destroyed. 
In transplanting woody plants in the open, special 
treatment is sometimes necessary, and it should be the 
aim of the grower to have the root system consist of a 
{Continued on page 322.) 
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