. Elementary principles of agriculture; a text book for the common schools . with freshly boiled well-water. The water should be boiled to drive out all the oxygen, and a layer of cooking oil used to prevent more being absorbed from the air. Insert cuttings of willow or Wandering Jew, and keep in a warm place for a week or more. Note the time when the rootlets appear on the cuttings. 68. Moisture Promotes Root Growth on Stems. A continu- ous supply of moisture stimulates root growth. Portions of stems kept in contact with moist soil for some time develop roots, as is often noticed in fallen co
. Elementary principles of agriculture; a text book for the common schools . with freshly boiled well-water. The water should be boiled to drive out all the oxygen, and a layer of cooking oil used to prevent more being absorbed from the air. Insert cuttings of willow or Wandering Jew, and keep in a warm place for a week or more. Note the time when the rootlets appear on the cuttings. 68. Moisture Promotes Root Growth on Stems. A continu- ous supply of moisture stimulates root growth. Portions of stems kept in contact with moist soil for some time develop roots, as is often noticed in fallen corn stalks, to- mato vines, and potatoes. To make roots develop on cuttings of roses, figs, grapes, etc., we bury them in moist sand, loam, or sawdust. (See ^ 194, Layerage.) 69. The Ideal Soil for cultivated plants is one having an abundant supply of moisture, containing plenty of soluble plant food, and so porous that air can circulate freely and come in contact with the roots. The soil may be too dense, or so compact that the air and water cannot circulate. It may be too wet,—that is, have so much water that all the air is forced out. In very wet weather, the roots are often noticed growing out of the surface of the ground. 70. Improving the Tilth of the Soil. We have already learned that the particles of the soil should be suffi- ciently fine for the root-hairs to grow between them. The particles may be so fine and so run together that neither the air nor the root-hairs can enter the soil. This condition is just as unfavorable for the roots as the coarse, lumpy soil. The texture, or physical con- Fig. 28. Arrangement for showing the effect of the exclusion of air on plant growth. A film of cooking oil prevents the boiled water from ab- sorbing oxygen from the air.
Size: 2193px × 2278px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauth, bookcentury1900, bookdecade1900, booksubjectagriculture
