Branching roots.
Fibrous roots.
The root, besides being a sort of stomach to the plant, is its support. The plant is fastened by it firmly in the ground. For this reason a large tree has a large and deep root. Its root branches out very much as the tree does above. It is shaped as you see here. But when the plant is quite small, and there is not much to be supported, the root is different. It is perhaps made up of fibres as seen in this figure. This is the case with the roots of grass, as you can see by pulling up some of it. In a piece of turf there are a great many spears of grass, and so it is full of these fibrous roots mingled together.
Some roots are made for still another purpose. Besides nourishingthe plant and supporting it, the root sometimes answers for food. When a root is intended for this use it is large. Look at the root of the beet. Here is a figure of it. The plant does not need so large a root as this to nourish and support it. The plant is nothing but a bunch of leaves, and with a very small root it would stand up in the ground. A small root, too, would answer to suck up all the sap that it needs. So small a plant could get along with a very small stomach.
You remember that in the chapter on seeds I told you that the seed-holder is sometimes larger than it need be to hold the seeds. The pear is a seed-holder, but it is larger than it need be if it were meant to be only a seed-holder. It is meant to be something else. It is fruit to be eaten as well as a seed-holder. It answers two purposes. So, too, when a root is larger than it need be to nourish the plant, it answers two purposes. Besides sucking up food for the plant, it answers as food for animals.
Beets and turnips.
In these large roots the mouths that suck up the sap are not in the body of the root. They are in the little fibres that are joined on to the main root, as you see in the beet. In the root of the turnip, as seen in this figure, there is a sort of tail going down into the ground from the bottom of it. The fibres, where the mouths are, make a part of this tail.
Runners.
In some plants roots are formed very curiously. Shoots start out and run along on the ground. After a little while these runners, as they are called, send down roots into the ground, as is here represented. The strawberry, you know, spreads in this way. So do the verbenas. When a runner gets fairly rooted it can live by itself, for it has a root, that is, a stomach of its own. You can separate it now from the main plant if you choose, and set it out somewhere else. This is done whenever we plant a new strawberry-bed.
Roots of dahlias.
This is a singular kind of root. It is spread out like a hand. Each of these fingers can be separated from the rest, and will grow by itself. The roots of the dahlias are of this kind.
Bulbs.
Some roots are bulbs, as they are called. The onion is a bulbous root. Below is one cut open. You see that it is all made up of coats, one inside of another, which you can peel off. The roots of hyacinths, lilies, blue-bells, and crocuses, are bulbs. These lie in the earth very still through all the winter. The life in them is asleep, just as it is in the buds. But it wakes up in the spring, and down go the roots from the bottom of the bulbs, and up come the plants from their tops. It is sometimes said that a bulb is really a bud, only itis in the ground, instead of being in the air as most buds are. Thus the onion is a bud, and the real roots of the plant are what you see branching down from the bottom of the bulb.
Slips of plants.
You have heard people talk about setting out slips. A slip is a branch of a plant. Some plants will grow from slips. Geraniums will. If you put a slip of geranium into the ground and keep it well watered, a root will shoot down into the earth from the end of the stem. And so the branch cut off becomes a growing plant. Before it was cut off it got its food with the other branches from the root of the plant to which it belonged. After it was cut off it could not live unless it could get a root of its own to suck up its food from the ground.
Duck-meat.
Most plants get their food from the ground. But some do not. Some get their food from water. This is the case with a plant called duck-meat, that is found in ponds and ditches where the water is still. You see little leaves on the surface of the water, and the roots hang like threads from the leaves. This is represented in this figure. Now there is something in the water in these places which is sucked up by these roots and makes the leaves grow. Sea-weed has no roots extending down into the ground, but it gets its nourishment from the water.
Hanging moss.
There are some plants that live on other plants. The mosses that you see on trees are plants of this kind. At the South there is a kind of gray moss that hangs down from the branches of trees, sometimes to a great length. It makes the land look as ifit were hung in mourning. The sap that nourishes this plant it gets from the bark of the trees. There are mouths in the moss where it hangs from the tree that suck in the sap which they find there.
Dodder, or love-vine.
The dodder, or love-vine, is a curious plant. It lives on other plants. It comes up out of the ground and clings to any plant that happens to be near it. After it is well fastened, and has grown considerably, its root in the ground dies. The little vine does not need it any longer, for it clings by real roots to the plant up which it runs. This is the reason that it is called love-vine; for, like love, it lives on that to which it clings. This vine has no leaves, and it is of a bright-yellow color. So it is sometimes called gold-thread vine.
Questions.—What is said about the root as a support for a tree? How is it with the roots of grass? What is said about roots that are for food? Tell about the root of the beet. Give the comparison made between roots and seed-holders. What is said of the root of the turnip? What of the roots of strawberries and verbenas? What of the roots of dahlias? What is said of bulbs? How do plants grow from slips? What is said about the duck-meat? What is said of mosses? Tell about the dodder.
Questions.—What is said about the root as a support for a tree? How is it with the roots of grass? What is said about roots that are for food? Tell about the root of the beet. Give the comparison made between roots and seed-holders. What is said of the root of the turnip? What of the roots of strawberries and verbenas? What of the roots of dahlias? What is said of bulbs? How do plants grow from slips? What is said about the duck-meat? What is said of mosses? Tell about the dodder.