SOILS 



hygroscopic water. Soil particles of cultivated lands 

 allow gravitational water to escape without resistance. 

 They permit capillary water to climb out of their reach, 

 even to be evaporated into the atmosphere, with some 

 reluctance, it is true, but withal, its freedom to go is 

 granted. But the last bit of film water the tiny covering 

 enclosing each wee particle is held fast so fast that no 

 force of gravity, no drying demand of warmth or heat or 

 sun is able to snatch away these many little shrouds in 

 their entiretv. 



WATER- HOLDING POWER OF SOILS 

 WHEN 100 POUNDS OF SOIL ARE USED 



SOIL 



V/ATER 



SAND 

 CLAY 

 HUMUS I 



-221bs. 

 551bs. 



Il431bs. 



VEGETABLE MATTER AIDS THE SOIL IN HOLDING WATER 



Water-holding capacity. When the pore-spaces of 

 the soil are filled with water, the soil is saturated. Every 

 bit of air has been driven out and for the time being the 

 soil is dead. In time if the soil has been properly han- 

 dled the excess water will be removed by gravitation 

 and by capillarity, the soil then will be in fit condition to 

 contribute its share to crop production ; for air, you 

 know, if good root development is to be had, is as neces- 

 sary as water. 



The amount of water that a soil holds will depend upon 

 several things, the following being of first importance : 



i. The nature or type of the soil : 



Sand soils receive and give off water freely, clays take 

 and give off slowly. 



