CHAPTER IV 

 RELATION OF SOILS TO WATER 



IMPORTANCE OF WATER TO PLANTS 



WE learned in a previous paragraph that plant 

 roots take moisture from the soil. What becomes 

 of this moisture? We will answer this question 

 with an experiment. 



Experiment. Take a pot or tumbler in which a 

 young plant is growing, also a piece of pasteboard 

 large enough to cover the top of the pot or tum- 

 bler; cut a slit from the edge to the centre of the 

 board, then place it on top of the pot, letting the 

 stem of the plant enter the slit. Now close the 

 slit with wax or tallow, making it perfectly tight 

 about the stem. If the plant is not too large invert 

 a tumbler over it (Fig. 21), letting the edge of the 

 tumbler rest on the pasteboard ; if a tumbler is not 

 large enough use a glass jar. Place in a sunny 

 window. Moisture will be seen collecting on the 

 inner surface of the glass. Where does this come 

 from? It is absorbed from the soil by the roots of 

 the plant and is sent with its load of dissolved plant 

 food up through the stem to the leaves. There most 

 of the moisture is passed from the leaves to the air 

 and some of it is condensed on the side of the glass. 



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