POOD 'i m. ri.wi i "M tii I soil 55 



CHAPTBB \. 'I'm: Food tin: I'i wt Takes from 

 tile Soil 



56. Water. — Ileal plants have only two sources from 

 which to draw their food — nanu -lv, the soil and the air. 

 From which of these sources do tlu-y draw their water? 

 Seed will not sprout in a perfectly dry soil. Deserts 

 produce almost no plants, and in time of continued 

 dronghl plants droop and finally die. It is evident that 

 soil to sj.n.ut seed and grow plants must contain water; 

 and from these facts we learn that plants draw their 

 water supply from the soil. 



By remembering that tbonl 76 per cent of meal 

 voting plants is moisture, we may form some Idea of the 

 vast amount Of water taken from the soil by many 

 crops. Suppose an acre of gronn produces a crop of 

 elov. r weighing ' r 6 tons; about 



80 per cent of this is water, or 9,600 pounds or 4.8 tons. 

 But this is not all the water an acre of clover requires 

 while it is growing. You m;iv drink a glass of water in 

 the morning, hut in a few hours you are again thirsty 

 and want more water. So with the clover; it is con- 

 stantly drinking n ad if not supplied the 

 crop withers and in time dies. Now, what becomes of 

 all the water which plants drink up from the soil? 

 i can hold only a certain amount, and as they are 

 constantly drinking it in, some must be given off. If 

 you will i fully t! of plants you will 



