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available plant food. Nitrification is more active when there is a 

 good tilth. The roots find their food more easily, as well as an 

 abundant supply of oxygen for the further preparation of supplies. 

 Soils lose their water by two means transpiration, that is, through 

 the leaves of plants, and evaporation from the surface of the soil. 

 The soil draws to the surface water from its deeper store by 

 capillary attraction. Ploughing and surface cultivation by widen- 

 ing the capillary tubes and breaking their continuity, lessens the 

 loss by capillary attraction. 



A well-tilled soil enables more plants to grow on the same 

 space of land, as the roots do not require to spread themselves in 

 search of supplies, but can go down deeper for them. Hoeing and 

 scarifying not only destroys the weeds but prevents too great an 

 evaporation from the surface of the soil by breaking up the con- 

 tinuity of the capillary tubes, and more air enters by the loosening 

 of the surface soil. A good tilth is necessary for the preparation 

 of a good seed bed. 



Lime improves land and increases its fertility by acting on the 

 insoluble potash compounds in the soil and liberating the potash. 

 It decomposes organic matter and promotes nitrification. It fixes 

 phosphoric acid in the soil. It neutralises the acidity in peaty soils, 

 and in soils that are deep and heavily charged with organic matter. 

 It specially improves clay soils by precipitating the fine floculen: 

 particles of the clay, and prevents it from puddling, thereby making 

 it easier to till. Lime should not be put into the land at the same 

 time as ammonia salts or nitrogenous organic matter, as this would 

 cause a great loss of nitrogen. Lime does no good in poor or 

 sandy soils ; in fact, it does them more harm than good, as these 

 soils, being poor in organic matter, the action of lime would be, by 

 reason of its rapid action on the organic matter, to make them 

 poorer still. If it is necessary that these poor soils should have 

 lime, it is best added as phosphate of lime or as gypsum. 



The best method of improving the soil is by a judicious appli- 

 cation of manure in conjunction with good tillage. The judicious 

 application of manure pre-supposes a knowledge of what elements 

 of the plant food are deficient in the soil. That information can be 

 obtained bv a chemical analyses, or by the field or plot analyses of 

 the soil. There is no soil, no matter how poor it may be, but can 

 be made fertile by the proper addition of manure. 



I have already spoken of the chemical analyses of the soil, and 

 will now describe the method of conducting the field <n- pl<>' 

 analyses. I'nder manures and manuring I describe the methods of 

 analysing the soil by lield or plot experiments for one class of crops. 

 It is'better and more thorough to test the soil with two classes of 

 crops, a deep rooted one and a surface feeder, such as wheat and 

 potatoes. It would slu.w at once whether the s il was deficient in 

 any of the plant foods for surface and deep-rooted feeders, 'flic- 

 experiments are made in the following manner : Kach plot to be 



