Secret plant

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  • Microbial biomass formation on root surfaces can be measured in plants growing in solution with or without an inert solid support. Carbon flow to the biomass can be measured by growing plants in solution or soil on a continuous source of 14C02 and the expected biomass formation predicted. The lack of correlation between measured and predicted biomass can be explained by oligotrophic growth of the micro-organisms.

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  • You have perhaps observed the regularity of arrangement in the twigs and branches of trees. Now pull up the roots of a plant, as, for example, sheep sorrel, Jimson weed, or some other plant. Note the branching of the roots. In these there is no such regularity as is seen in the twig. Trace the rootlets to their finest tips. How small, slender, and delicate they are! Still we do not see the finest of them, for in taking the plant from the ground we tore the most delicate away. In order to see the real construction of a...

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  • In the preceding chapter advice is given that applies to groups or classes of plants, and many lists are inserted to guide the grower in his choice or at least to suggest to him the kinds of things that may be grown for certain purposes or conditions. It now remains to give instructions on the growing of particular kinds or species of plants. It is impossible to include instructions on any great number of plants in a book like this. It is assumed that the user of this book already knows how to grow the familiar or easily handled...

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  • We have hitherto examined what is called the ultimate division of plants. That is, we have looked at each one of the elements separately, and considered its use in vegetable growth.[Pg 44] Of what do wood, starch and the other vegetable compounds chiefly consist? Are their small ashy parts important? What are these compounds called? Into how many classes may proximate principles be divided? Of what do the first class consist? The second? What vegetable compounds do the first class comprise? We will now examine another division of plants, called their proximate division.

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  • The object of cultivating the soil is to raise from it a crop of plants. In order to cultivate with economy, we must raise the largest possible quantity with the least expense, and without permanent injury to the soil. Before this can be done we must study the character of plants, and learn their exact composition. They are not created by a mysterious power, they are merely made up of matters already in existence. They take up water containing food and other mat[Pg 12]ters, and discharge from their roots those substances that are not required for their growth. ...

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  • Plants are preyed on by insects and fungi; and they are subject to various kinds of disease that, for the most part, are not yet understood. They are often injured also by mice and rabbits (p. 144), by moles, dogs, cats, and chickens; and fruit is eaten by birds. Moles may be troublesome on sandy land; they heave the ground by their burrowing and may often be killed by stamping when the burrow is being raised; there are mole traps that are more or less successful. Dogs and cats work injury mostly by walking across newly made gardens or...

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  • There is a knack in the successful handling of plants that it is impossible to describe in print. All persons can improve their practice through diligent reading of useful gardening literature, but no amount of reading and advice will make a good gardener of a person who does not love to dig in a garden or who does not have a care for plants just because they are plants. To grow a plant well, one must learn its natural habits. Some persons learn this as if by intuition, acquiring the knowledge from close discrimination of the behavior of the...

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  • The great depth and high fertility of the soils of arid and semiarid regions have made possible the profitable production of agricultural plants under a rainfall very much lower than that of humid regions. To make the principles of this system fully understood, it is necessary to review briefly our knowledge of the root systems of plants growing under arid conditions.

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  • Plants have diseases just as animals do; not the same diseases, to be sure, but just as serious for the plant. Some of them are so dangerous that they kill the plant; others partly or wholly destroy its usefulness or its beauty. Some diseases are found oftenest on very young plants, others prey on the middle-aged tree, while still others attack merely the fruit. Whenever a farmer or fruit-grower has disease on his plants, he is sure to lose much profit. You have all seen rotten fruit. This is diseased fruit. Fruit rot is a plant disease. It costs...

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  • Let us now examine plants with a view to learning the location of the various plants. The stem or trunk of the plant or tree consists almost entirely of woody fibre; this also forms a large portion of the other parts except the seeds, and, in some instances, the roots. The roots of the potato contain large quantities of starch. Other roots such as the carrot and turnip contain pectic acid,[J] a nutritious substance resembling starch.

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  • If you partly burn a match you will see that it becomes black. This black substance into which the match changes is called carbon. Examine a fresh stick of charcoal, which is, as you no doubt know, burnt wood. You see in the charcoal every fiber that you saw in the wood itself. This means that every part of the plant contains carbon. How important, then, is this substance to the plant! You will be surprised to know that the total amount of carbon in plants comes from the air. All the carbon that a plant gets is taken...

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  • We have hitherto examined what is called the ultimate division of plants. That is, we have looked at each one of the elements separately, and considered its use in vegetable growth.[Pg 44] Of what do wood, starch and the other vegetable compounds chiefly consist? Are their small ashy parts important? What are these compounds called? Into how many classes may proximate principles be divided? Of what do the first class consist? The second? What vegetable compounds do the first class comprise? We will now examine another division of plants, called their proximate division.

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  • It will be recollected that, in addition to its mineral portions, the soil contains organic matter in varied quantities. It may be fertile with but one and a half per cent. of organic matter, and some peaty soils contain more than fifty per cent. or more than one half of the whole. The precise amount necessary cannot be fixed at any particular sum; perhaps five parts in a hundred would be as good a quantity as could be recommended. The soil obtains its organic matter in two ways. First, by the decay of roots and dead plants, also of...

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  • The large amount of water required for the production of plant substance is taken from the soil by the roots. Leaves and stems do not absorb appreciable quantities of water. The scanty rainfall of dry-farm districts or the more abundant precipitation of humid regions must, therefore, be made to enter the soil in such a manner as to be readily available as soil-moisture to the roots at the right periods of plant growth. In humid countries, the rain that falls during the growing season is looked upon, and very properly, as the really effective factor in the production of large...

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  • All plants when carefully burned leave a portion of ash, ranging widely in quantity, averaging about 5 per cent, and often exceeding 10 per cent of the dry weight of the plant. This plant ash represents inorganic substances taken from the soil by the roots. In addition, the nitrogen of plants, averaging about 2 per cent and often amounting to 4 per cent, which, in burning, passes off in gaseous form, is also usually taken from the soil by the plant roots. A comparatively large quantity of the plant is, therefore, drawn directly from the soil. Among the ash...

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  • How do plants obtain their hydrogen and oxygen? Let us now consider the three gases, hydrogen, oxygen and nitrogen, which constitute the remainder of the organic part of plants. Hydrogen and oxygen compose water, which, if analyzed, yields simply these two gases. Plants perform such analysis, and in this way are able to obtain a sufficient supply of these materials, as their[Pg 24] sap is composed chiefly of water.

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  • PLANT CELLS, UNLIKE ANIMAL CELLS, are surrounded by a relatively thin but mechanically strong cell wall. This wall consists of a complex mixture of polysaccharides and other polymers that are secreted by the cell and are assembled into an organized network linked together by both covalent and noncovalent bonds. Plant cell walls also contain structural proteins, enzymes, phenolic polymers, and other materials that modify the wall’s physical and chemical characteristics.

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  • Nitric oxide enhances salt secretion and Na+ sequestration in a mangrove plant, Avicennia marina, through increasing the expression of H+-ATPase and Na+/H+ antiporter under high salinity.

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  • The work of the dry-farmer is only half done when the soil has been properly prepared, by deep plowing, cultivation, fallowing, for the planting of the crop. The choice of the crop, its proper seeding, and its correct care and harvesting are as important as rational soil treatment in the successful pursuit of dry-farming. It is true that in general the kinds of crops ordinarily cultivated in humid regions are grown also on arid lands, but varieties especially adapted to the prevailing dry-farm conditions must be used if any certainty of harvest is desired. Plants possess a marvelous power...

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  • The demonstration in the last chapter that the water which falls as rain or snow may be stored in the soil for the use of plants is of first importance in dry-farming, for it makes the farmer independent, in a large measure, of the distribution of the rainfall. The dry-farmer who goes into the summer with a soil well stored with water cares little whether summer rains come or not, for he knows that his crops will mature in spite of external drouth. In fact, as will be shown later, in many dry-farm sections where the summer rains are...

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