tailieunhanh - DEFICIENCIES OF SOILS, MEANS OF RESTORATION, ETC

As will be seen by referring to the analyses of soils[Pg 156] on p. 72, they may be deficient in certain ingredients, which it is the object of mineral manures to supply. These we will take up in order, and endeavor to show in a simple manner the best means of managing them in practical farming. ALKALIES. POTASH. Do all soils contain a sufficient amount of potash? How may its deficiency have been caused? How may its absence be detected? Does barn-yard manure contain sufficient potash to supply its deficiency in worn-out soils? Potash is often deficient in the. | DEFICIENCIES OF SOILS MEANS OF RESTORATION ETC As will be seen by referring to the analyses of soils Pg 156 on p. 72 they may be deficient in certain ingredients which it is the object of mineral manures to supply. These we will take up in order and endeavor to show in a simple manner the best means of managing them in practical farming. ALKALIES. POTASH. Do all soils contain a sufficient amount of potash How may its deficiency have been caused How may its absence be detected Does barn-yard manure contain sufficient potash to supply its deficiency in worn-out soils Potash is often deficient in the soil. Its deficiency may have been caused in two ways. Either it may not have existed largely in the rock from which the soil was formed and consequently is equally absent from the soil itself or it may have once been present in sufficient quantities and been carried away in crops without being returned to the soil in the form of manure until too little remains for the requirements of fertility. In either case its absence may be accurately detected by a skilful chemist and it may be supplied by the farmer in various ways. Potash as well as all of the other mineral manures is contained in the excrements of animals but not as is also the case with the others in sufficient quantities to restore the proper balance to soils where it is largely Pg 157 deficient nor even to make up for what is yearly removed with each crop except that crop or its equivalent has been fed to such animals as return all of the fertilizing constituents of their food in the form of manure and this be all carefully preserved and applied to the soil. In all other cases it is necessary to apply more potash than is contained in the excrements of animals. What is generally the most available source from which to obtain this alkali Will leached ashes answer the same purpose How may ashes be used Unleached wood ashes is generally the most available source from which to obtain this alkali. The ashes of all .