404 



How Living Things Affect One Another unit vii 



Fig. 356 Not siiiuke, but dust whipped up jrovi barren land. Introducmg plants that 

 bind the soil helps prevent this. (u. s. soil conservation service) 



Fig. 357 Contour planting on slopes in South Carolina. Can you see what else has 

 been done here to save topsoil? 



