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soil should be neither too loose nor too compact. If it is 

 either composed entirely of sand or entirely of clay, it 

 cannot well be termed highly fertile ; but, when made up 

 of a mixture, partly sand and partly clay, to which is 

 added plenty of humus, or organic matter in an advanced 

 state of decomposition, and also a variety of mineral sub- 

 stances, it forms a substantial basis of fertility. 



Humus is a very necessary component part of a fertile 

 soil, which, by its presence, is rendered light and porous 

 in texture, capable of readily absorbing and retaining 

 much moisture, and suitable for the rapid development and 

 extension of systems of plant roots. 



Finally there remains to be mentioned another element 

 of fertility, by far the most important of them all. It 

 exists in different soils in widely varying quantities. In- 

 deed, the amount to be found in any one soil at different 

 seasons varies within wide limits. Now it is large, and 

 then again very small. Without this element a soil in 

 other respects most fertile would be useless as the abode 

 of plant life. What is this all important factor ? It is 

 water. 



WATER. 



Common, abundant, and cheap as it is, yet water in the 

 right quantity and form must be regarded as a prime 

 requisite toward making a fertile soil. It forms the major 

 portion of all organic life, both animal and vegetable. The 

 plant is mainly water. Therefore no plant can long grow 

 without plenty of water. But the soil needs to be moist 

 in distinction from being actually wet or soaked with 

 water. If its pores were constantly filled with water, the 

 air would be excluded, and fertility out of the question, 

 since a proper degree of aeration of the soil is an absolute 

 necessity for the growth of crops. The water table, or 

 surface of the ground water, needs to be deep in the sub- 

 soil, several feet below the surface of the ground. From 



