MAKING THE SOIL PRODUCE CROPS 



state of solution, they cannot be absorbed by 

 plant roots. Lime is a potent force in creating 

 chemical reactions in the soil, resulting in the 

 stimulation of growth through increased absorp- 

 tion of essential elements in solution. 



Lime also benefits soils of a clayey nature 

 through its ability to cement together the fine 

 clay particles and in that way create air spaces 

 so greatly needed in tight clay soils. Lime is 

 beneficial, too, in the case of soils which have a 

 large proportion of sand or large particles, and 

 serves as an agent in creating a better condition 

 of tilth and of moisture retention. 



It makes little difference in what form lime 

 is applied. It may be purchased and applied in 

 the form of ground limestone, a rock rich in 

 calcium which has been mechanically ground 

 to a very great degree of fineness. It can also 

 be applied in the form of hydrated lime. This 

 is obtained by heating ground limestone and 

 slaking it by adding water. A common example 

 of this is the slaking of lime for whitewashing 

 purposes. Another good source of lime is finely 

 ground shells of oysters or other forms of sea 

 life which collect the calcium from sea water and 

 deposit it in their shells. 



Adjusting the Water Content of Soils. Aside 

 from the supplying of water by irrigation, a 

 rather costly process under most conditions, 



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