THE SO/L 23 



of its weight of water; and clay can hold more than So 

 per cent. 



When a soil takes up as much as 80 per cent of its 

 weight of water, the water often completely fills the spaces 

 between the particles of soil, driving out all the air. The 

 roots of most plants cannot live in a soil without air. 

 Therefore, clay is a difficult soil for plants to grow in. 



What is the origin of the soil in your garden? What is its structure 

 (sand, loam, or clay) ? Why is loam usually a better soil than clay ? 

 Why better than sand? At what time of year is sand likely to be best 

 as a soil ? Do you know any wild plants that grow only in sand ? 



