Root (plant)

“ Fig. 83-85. Forms of tap-root.
74. Fleshy Roots are those in which the root becomes a storehouse of nourishment. Typical roots of this kind are those of such biennials as the turnip and carrot; in which the food created in the first season's vegetation is accumulated, to be expended the next season in a vigorous growth and a rapid development of flowers, fruit, and seed. By the time the seed is matured the exhausted root dies, and with it the whole plant. ”

“ STEMS AND SEED LEAVES The smaller plants usually have green stems. The larger ones have brown, woody stems, such as you see in bushes and trees; for the trunk of the biggest tree in the world is nothing but a great stem.
The delicate green stems die down to the ground during the cold winter. Sometimes the whole plant [Pg 120] dies, the root below as well as the stem above ground. But often the root (or what we usually call the root) lives, and sends up a fresh stem the next year. ”

“ Fig. 46.—Root-hair, much enlarged, in contact with the soil particles (s) . Air-spaces at a; water-films on the particles, as at w.
The root-hairs are very small, often invisible. They, with the young roots, are usually broken off when the plant is pulled up. They are best seen when seeds are germinated between layers of dark blotting paper or flannel. On the young roots they will be seen as a mould-like or gossamer-like covering. Root-hairs soon die: they do not grow into roots. New ones form as the root grows. ”

“ Once it finds itself firmly rooted in the stem of its victim, it begins to grow vigorously. With every few inches of its growth it sends new roots deep into this stem. And when it feels quite at home, and perfectly sure of its board, it begins to wither away below, where it is joined to its earth root. Soon it breaks off entirely from this, and draws every bit of its nourishment from the plant or plants in which it is rooted. ”

“ No two roots are alike; that is, they vary among themselves as stems and leaves do. Each kind of plant has its [37] own form or habit of root (Fig. 39) . Carefully wash away the soil from the roots of any two related plants, as oats and wheat, and note the differences in size, depth, direction, mode of branching, number of fibrils, colour, and other features. The character of the root system often governs the treatment that the farmer should give the soil in which the plant or crop grows. ”

“ Roots are most easily extricated from light soil, and with least fracture. They are large in proportion to stem in dry soil and climate, and when they are situated near the surface of the ground.—A healthy growing plant, of firm fibre, large root, and sturdy short stem of one leader and numerous feeders, is the great desideratum: a large root is the more desirable, as a considerable part of it is generally broken off in transplanting, rendering it disproportioned to the top, which, in consequence, either languishes, or receives deterring cropping. ”

“ The root of a young plant grows downward into the soil under the influence of gravity. Its tip, which has to force its way through the rough material of sand and clay, is beautifully protected by a special root-cap, which covers the growing point as with a cushion. The surface of the root-cap is slimy, to aid it in slipping forward, and its cells, which are being worn away constantly, are replaced by the growth of the interior. ”

“ After the plants have flowered they should be cut down, and they will reappear in the autumn. They have long tap-roots that are easily injured, but where they flourish they spread laterally—that is, they send up young plants at the side. These you can take up. Whenever a plant has a root like a carrot, it is called a ‘tap-root,’ and you must be careful not to break it. ”

“ The leaves of the root are large and stalked, oval, lance-shaped, and wrinkled; those of the stems are stalkless, and so attached as to give the stems a winged appearance near their junction.
The plant will thrive in any kind of soil, but it likes shade and moisture, and a specimen grown under such conditions will be found to be much superior in every way. A position under fruit trees suits it admirably, and for such thoughtful planting it will well repay the lover of flowers for vase decoration. ”

“ The root holds the plant firmly in the ground and takes in water and mineral matter from the soil; the stem holds the leaves up to the light and acts as a pathway for fluids between the root and leaves; the leaves, under certain conditions, manufacture food for the plant and breathe; the flowers form the fruits; the fruits hold the seeds, which in turn hold young plants which are capable of reproducing adult plants of the same kind. ”

“ If the root produce too many branches or arms, cut away the weakest of them, and leave none but 3. or 4. of the strongest and most vigorous, and such as have their knots nearest to one another. When I transplant my Melons from the Nursery-bed, I put commonly two roots together, except I find one very strong, which I then plant alone, cutting from it neither of the branches that shoot from each side (mark't 7.7.) ”

“ Let us fix our attention on a single plant. It has a certain amount of root pasturage and space in which to grow. Since it is not permitted to produce an indefinite number of young plants, it begins to develop itself. The soil is rich, the roots are busy, and there must be an outlet. The original plant cannot form others, and therefore begins to produce fruit-crowns for the coming year. All the sap, all the increasing power of root and foliage, are directed to preparation for fruit. ”

“ Some roots last one year, others two, and others, like the shrubs and trees which they produce, have an indefinite period of existence; but they all consist of a collection of fibres, composed of vascular and cellular tissues, without tracheæ, or breathing-vessels. The stem is the grand distributor of the nourishment taken by the roots to the various parts of the plant. The seat of its vitality is in the point or spot called the neck, which separates the stem from the root. If the root of a young plant be cut off, it will shoot afresh; if the stem be taken away it will be renewed. ”

“ The most prominent of these parts are root, stem, leaf, flower, fruit, and seed. Familiar plants differ wonderfully in size and shape,—from fragile mushrooms, delicate waterweeds and pond-scums, to floating leaves, soft grasses, coarse weeds, tall bushes, slender climbers, gigantic trees, and hanging moss.
The Stem Part.—In most plants there is a main central part or shaft on which the other or secondary parts are borne. This main part is the plant axis. Above ground, in most plants, the main plant axis bears the branches, leaves, and flowers; below ground, it bears the roots. ”

“ In fact they should be regarded as the guy-ropes of a flagstaff, intended to hold the plant firm from all points. If a root is too long to lie at its full length in the hole, instead of trying to fit it in against its natural inclination by turning it round the side of the hole, a further little channel must be dug in which it can lie perfectly flat. And great care must be taken not to injure the little white, fibrous rootlets, which mean flowering strength for the coming season. ”

“ The final causes of many of these facts are easy to comprehend: the reason why a root grows down into the earth, is for the purpose of obtaining that sustenance which is necessary for the growth of the plant of which it is a part; and stems grow upwards, and towards the light, because the influence of this element is necessary for the elaboration of the sap; as a result of which process, stems grow in thickness, roots in length, flowers are developed, and the proper juices of vegetables become formed. ”

“ The entire mass of roots of any plant is called its root system. The root system may be annual, biennial or perennial, herbaceous or woody, deep or shallow, large or small.
Kinds of Roots.—A strong leading central root, which runs directly downwards, is a tap-root. The tap-root forms [33] an axis from which the side roots may branch. The side or spreading roots are usually smaller. Plants that have such a root system are said to be tap-rooted. Examples are red clover, alfalfa, beet, turnip, radish, burdock, dandelion, hickory (Figs. 32, 33) . ”

“ If you repeat this often with many plants you will find that these are the actively growing parts of the stems and roots; the individual leaves, of course, are also growing. Thus we see that growth is not a simple stretching of the whole, but that there are two definite regions where it is specially active. That of the stem and first root carry on the growth in opposite directions, as we noticed before (see p. 11) , the normal stem growing up into the air and the root down into the soil. ”

“ The plant may at once be recognized by the heart-shaped pods and small, white, four-petaled flowers. The plant begins to flower when very small, but continues to grow until it forms a much-branching plant, half a metre or more in height. On pulling up the plant, a large tap-root (Fig. 93, A, r) is seen, continuous with the main stem above ground. The first root of the seedling plant continues here as the main root of the plant, as was the case with the gymnosperms, but not with the monocotyledons. ”

“ The protoplasmic lining of the cell wall is such a membrane. The soil water being a weaker solution than the sap in the roots, the flow is into the root. A strong fertilizer sometimes causes a plant to wither, or “burns it.” Explain.
Structure of Roots.—The root that grows from the lower end of the caulicle is the first or primary root. Secondary roots branch from the primary root. Branches of secondary roots are sometimes called tertiary roots. Do the secondary roots grow from the cortex, or from the central cylinder of the primary root? ”

“ Passion Flower.—Cuttings of the young shoots strike readily in sand under glass. The plant likes a good loamy soil mixed with peat. A sheltered position with a south or south-western aspect should be assigned those grown out of doors, and the root should be well protected in winter. The flowers are borne on seasoned growth of the current year: this fact must be considered when pruning the plants. During the hot months the roots require a copious supply of water, and the foliage should be syringed freely. ”

“ The root has little mouths in its branches every where. It is by these that the food of the plant is sucked up. They are so small that you can not see them without a powerful microscope. They are in the fine parts or fibres of the root that you see hanging to the main branches of it when you take up a root. ”

“ Should an obstacle such as a pebble be encountered, a root will bend round it and then return to its former direction. Branch roots are given off on{106} all sides at an angle to the main stem, these also tending in a mysterious way, if their course is disturbed by an obstacle, to resume their former direction of growth; the branches again divide, till at length a complicated root-mass is formed, sometimes of great extent, and capable of extracting water from a large volume of soil. ”

“ The roots grow here and there in search of food, often extending much farther in all directions than the spread of the top of the plant. Roots tend to spread farther in poor soil than in rich soil, for the same size of plant. The root has no such definite form as the stem has. Roots are usually very crooked, because they are constantly turned aside by obstacles. Examine roots in stony soil. ”

“ I wonder if these green leaves will not look more beautiful than ever when we think of the work they are doing.
144 ROOT CELLS. Roots do their work underground as a rule.
You might prefer not to be a root, if you had your choice; you might prefer to be a leaf or a flower.
I have never heard that the roots complained of their work, however. For one thing, it is easier. All they have to do is to hold the plant fast, suck up juices from the earth, and in some cases store away food material,—that is, if they are regular, well-behaved, everyday, underground roots. ”

“ In the last edition of the 'Pemptades ' of Dodoens [9] of the year 1616, a folio volume of 872 pages, only one page and a third are devoted to the explanation of the parts of plants; but the selection of the words explained and the substance of the explanations hit the essential points better than in Fuchs. We find for instance: Root ('radix, ῥιςα') is the name given in the tree and in every other plant to the lower part, by which it penetrates into the earth and cleaves to it, and by which it draws its nourishment. ”

“ Each little thread makes it just so much the more difficult to uproot the plant.
I think you know already that another use of the root is to obtain nourishment for the plant.
These thread-like roots, you notice, creep out on every side in their search for food and drink. The water they are able to suck in easily by means of tiny mouths, which we cannot see. But the plant needs a certain amount of earth food, which in its solid state could not slip down these root throats any more easily than a young baby could swallow a lump of sugar. ”

“ In the first place, the sun warms the ground in which the seed lies buried. Then the seed swells and bursts, and sends downward a little root; the root drinks in the water from the soil, and so gets larger, and spreads around; and by-and-by it sends up a stem above the ground. As soon as the sunlight falls on the little plant, it gets stronger, and is able to take food as well as drink from the soil, so as to get its full shape and size and green color. ”

“ The activity of the functions of the plant having been greatly diminished in the leaves, the root system is correspondingly stimulated, and will produce new shoots, which by their absorbing power, will contribute greatly to the vigor of the young plant. The breaking of the extreme ends of the roots, occasions no harm since the absorbent surface of the roots is confined to the parts provided with hairs, which are found in the middle of the young fibers. ”