CHAPTEE VI 



PLANTS IN RELATION TO SOIL, LIGHT 

 AND AIR 



The intimate relations existing between plants and their 

 surrounding elements may be clearly shown by means of such 

 simple exercises as those suggested in this chapter. 



I. Absorbing Moisture. — ^Arrange two pots or cans inside two 

 small lard pails as shown in figure 35. The two flower pots are 

 filled alike with the same kind of good garden soil. A few kernels 

 of corn are planted in one of them. After the corn is a few inches 



Fig. 36. 



Fig. 35. 



Fig. 35. — Two pots of soil are immersed in the same amount of water in the 

 outer vessels. Corn is grown in one pot but none in the other to see the difference 

 in evaporation. (U. S. D. A.) 



Fig. 36. — Plants grown in glass bottles wrapped in dark paper to exclude the light. 

 When the wrapping is removed the root system is exposed to ^'iew. 



high, have the water in the lard pails filled to the line shown in the 

 figure. Keep it filled daily up to the mark, and note the amount 

 required for each pail in a week. The one wltli the growing plants 

 will require the most, because of the water taken up by the growing 

 plants. 



The growth of plants cannot take place without the use of 

 water taken up through their roots. This water comes from 

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