SOIL IMPROVEMENT 77 



when there is plenty of lime in the soil. Lime should be 

 applied to the soil when heavy crops are plowed under. 

 Heavy applications of green manure also have a drying 

 effect upon the soil, and there may then be more suffering 

 at time of drought. 



Benefits of Lime. In another chapter the character of 

 limestone soils was discussed. (Pages 53-54.) It is a good 

 practice to spread lime on soils for certain crops just as 

 fertilizer is applied. The benefits derived from the addition 

 of lime to soils are here enumerated : 



It aids decay of vegetable matter. 



It helps liberate plant-foods in the soils. 



It hastens the growth of bacteria in the soil. 



The heavy clay soils are made more open, porous, and 

 more easily tilled; moisture and air move more freely; the 

 soil will then become warmer in early spring. 



The light sandy soils are made more compact, and hold 

 moisture better. 



Lime acts upon acids in soils and destroys the sourness; 

 this is a benefit for nearly all farm crops. 



It is a direct plant-food for alfalfa and some other mem- 

 bers of the clover family. 



EXERCISE. Slaking Lime. Expose a small lump of 

 burned lime, called quick-lime, on a board or paper, for a 

 day or more until it crumbles to powder. This powder is 

 then called air-slaked lime. A second lump of quick-lime 

 may be placed in a dish and wet with a very little water 

 from time to time until it heats and crumbles. When burned 

 lime is used on soil, it should be air-slaked before spreading. 

 A little water added to it will hasten the slaking. 



EXERCISE. To Study Lime-water. Slake some fresh 

 lime the size of a baseball by pouring water over it very 

 slowly until it crumbles. Then cover it well with water 

 and stir. After it is allowed to settle, pour off the clear 

 water. Put in a strip of red litmus paper and note the result. 



