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Show TILLAGE OF D3Y LAND Operation of Loosening and Stirring Stir-ring of Soil. hallow Cultivation Checks Rapid Loss of Water From Surface, Kills Weeds and Aids in Admitting Air to Top Layer. The operation of loosening and stir-Mng stir-Mng the soil is usually spoken of as tillage or cultivation. Tillage includes in-cludes both the preparation before planting and the working of the soil after the crop is planted, while cultivation culti-vation includes only the stirring of the soil after the crop has been planted. For moist soils it is best to practice prac-tice deep tillage in the preparation of the seed bed and shallow cultivation after ;he crop Is planted. Deep tillage till-age gives the pl-nnts a large amount of room in which to send their roots in search of plant food, allows the soil to drink in the rainfall more freely, free-ly, and permits the air to enter the soil and help In the preparation of plant food. Shallow cultivation checks the rapid loss of water from its surface, sur-face, kills weeds, and helps to admit air to the surface layer of soil. Plants are like animals in that they must have food and drink or they soon sicken and die. Animals can. move about from place to place and secure their food, but plants must get their food and water by sending their roots out into the soil. The tiny roots which spread out through the soil are busy all of the time taking up water wa-ter from the soil for the use of the stalk and leaves above. This water, as it goes Into the plant through the roots, carries with It the plant food which it has dissolved out of the little soil particles. Place a lump of salt in a glas3 of water and stir for a few minutes. The salt disappears, and you will find that the water has a salty taste. The salt has dissolved in the water, and we say that the salt is in solution In the water. wa-ter. All of the food which comes from the soil must be in solution before it can be used by the plant. The water that goes in through the roots presses out through the leaves into the air and leaves the plant food behind to build up the tissues of the plant. If the soil Is hard and lumpy the little lit-tle roots can penetrate far into it, but must feed near the surface. If we have a deep, mellow seed bed, the roots are encouraged to go deep and gather plant food from a large amount of soil. The plant food in hard, lumpy ground is not easily dissolved. Stirring Stir-ring the soil and breaking up the clods bring the water ...into contact with more soil surface and hastens the solution of the plant food. The depth to which the 'soil should be prepared depends upon the depth I to which the plant roots will penetrate. pene-trate. Wheat, oats and other small grains are shallow rooted and do not need so deep a seed bed as corn or root crops. Soils that have always been plowed shallow should be deepened gradually by setting the plow to go about one Inch deeper each season until a depth of eight or nine inches has been reached. reach-ed. If this deepening is not done gradually, the soil will be injured and poor crops will result for several seasons. sea-sons. About one-third of the total space occupied by sand and about one-half of that taken up by clay is occupied by the soil particles themselves, and the other half Is taken up by air, if the soil be dry. For the best growth of crops about half of the space not occupied by soil should be equally divided di-vided between air and water. If the soil Is not drained this space becomes be-comes entirely filled with water, and the plants whose roots are feeding In the soil are suffocated from lack of air and oxygen. Some plants, such as the cypress and water lily, have special spe-cial structures which enable them to obtain their oxygen from the air and water, while their roots are entlretj under water, but our common field plants do not have this power. Soils that are quile sandy and gravelly may allow the water to pass downward too rapidly and thus deprive the plants of needed moisture. In such cases it is neoessnry to treat the land In such a way th-it Its water holding capacity is increased This may be done by plowing under stable manure or anv well rotted vegetable matler, which assists the soil to hold water like a sponge. In the heavy soils the water passes downward so slowly that plants In their early, growth send out only a very shallow root system, because the free water Is so near the surface and because the common field plants will not send their roots into free water In time the water makes its way far below the roots of the plant; a drought comes on. and the plant dies or shrivels, because the root system In its early life did not extend deep enough to find the film water (that is. a thin water coating on the soil grains), which would supply It during the dry season. |