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      FIG. 2.

       The first effort of a sprouting seed is to send a root down into the soil.ToList

      FIG. 3.

       Germinating seeds produce roots before they send a shoot up into the air.ToList

      Which part of any or all of these farm plants is of greatest importance to the plant itself?

      I am sure that you will agree that the root is the part most important to the plant itself, for if any part of a plant be separated from the root, that part ceases growth and will soon die, unless it is able to put out new roots. But the root from which the plant was cut will generally send up new shoots, unless it has nearly completed its life work. When a slip or cutting is placed in water or in moist sand it makes a root before it continues much in growth. When a seed is planted its first effort is to send a rootlet down into the soil.

      Experiment to see if this is true by planting slips of willow, or geranium, or by planting corn or beans in a glass tumbler of soil, or in a box having a glass side, placing the seeds close to the glass; then watch and see what the seed does. Figs. 2 and 3.

      Which of the parts of the plant is of greatest importance to the farmer or any plant grower, or to which part of a plant should the plant grower give his best attention? You will probably mention different parts of the different plants in answering this question. For instance, some will say, "The seed is the most important part of the wheat plant to the farmer, for that is what the wheat is grown for." "The fruit is the most important part of the apple plant for the same reason." "The leaves and grain of the corn, the leaves of the cabbage, are the important parts of these plants and should have the best attention of the grower, because they are the parts for which he grows the plants." But you must remember that all of these parts are dependent on the root for life and growth, as was brought out in the answer to the last question, and that if the farmer or plant grower desires a fine crop of leaves, stems, flowers, fruit or seeds, he must give his very best attention to the root. Judging from the poor way in which many farmers and plant growers prepare the soil for the plants they raise, and the poor way they care for the soil during the growth of the plants, they evidently think least of, and give least attention to, the roots of the plants.

      Then, in studying our plants, which part shall we study first? Why, the roots, of course: To find out what they do for the plant, how they do this work, and what conditions are necessary for them to grow and to do their work well.

      

       Table of Contents

       Table of Contents

      USES OF ROOTS TO PLANTS

      Of what use are roots to plants, or, what work do they perform for the plants?

      If the reader has ever tried to pull up weeds or other plants he will agree that one function of the roots of plants is to hold them firmly in place while they are growing.

      Experiment.—Pull two plants from the soil, shake them free of earth, and place the roots of one in water and expose the roots of the other to the air. Notice that the plant whose roots are exposed to the air soon wilts, while the one whose roots were placed in water keeps fresh. You have noticed how a potted plant will wilt if the soil in the pot is allowed to become dry (see Fig. 4), or how the leaves of corn and other plants curl up and wither during long periods of dry weather. It is quite evident roots absorb moisture from the soil for the plant.

      Experiment.—Plant some seeds in tumblers or in boxes filled with sand and in others filled with good garden soil. Keep them well watered and watch their progress for a few weeks (see Fig. 5). The plants in the garden soil will grow larger than those in the sand. The roots evidently must get food from the soil and those in the good garden soil get more than those in the poorer sand. Another important function of plant roots then is to take food from the soil for the plant.

      You know how thick and fleshy the roots of radishes, beets and turnips are. Well, go into the garden and see if you can find a spring radish or an early turnip that has sent up a flower stalk, blossomed and produced seeds. If you are successful, cut the root in two and notice that instead of being hard and fleshy like the young radish or turnip, it has become hollow, or soft and spongy (see Fig. 6). Evidently the hard, fleshy young root was packed with food, which it afterwards gave up to produce flower stalk and seeds.

      A fourth use of the root, then, is to store food for the future use of the plant.

      Experiment.—Plant a sweet potato or place it with the lower end in a tumbler of water and set it in a warm room. Observe it from day to day as it puts out new shoots bearing leaves and roots (see Fig. 7). Break these off and plant them in soil and you have a number of new plants. If you can get the material, repeat this experiment with roots of horse-radish, raspberry, blackberry or dahlia. From this we see that it is the work of some roots to produce new plants. This function of roots is made use of in propagating or obtaining new plants of the sweet potato, horse-radish, blackberry, raspberry, dahlia and other plants.

      FIG. 4.

       To show that plant-roots take water from the soil, the plants in A are suffering from thirst. B has sufficient water.ToList

      FIG. 5.

       To show that plant-roots take food from the soil. Both boxes were planted at the same time.ToList

      FIG. 6.

       A radish root, from which the stored food has been used to help produce a crop of seeds.

       Notice the spindle shaded seed-vessels.ToList

      FIG. 7.

       A sweet-potato root producing new plants.ToList

      We have now learned five important things that roots do for plants, namely:

      Roots hold plants firmly in place.

      They absorb water from the soil for the plants.

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