78 



SOIL AND ITS RELATION TO ROOTS 



Observations. — Tabulate the exact amount of water left in 

 the soil in each case. 



Conclusion. — 1. Of what use is the forest covering of leaf 

 mold? 



2. Which kinds of soils would be most favorable for crops and 

 why? 



Problem 60: WTiat do plants take out of the soil f 

 Materials. — Glass jars, distilled water, nutrient solution, corn 

 seedlings. 



Method. — Partly fill five jars, the first with distilled water, 

 the second with nutrient solution ^ without potassium nitrate, a 

 third with nutrient solution without calcium phosphate, the 

 fourth with nutrient solution without ferric chloride, and a fifth 

 with nutrient solution. Place in the jars corn seedlings with their 

 roots in the liquids. Keep them under observation for two or 

 more weeks. 



' A nutrient solution known as Sach's solution may be made as follows : 



Potassium Nitrate 1.00 gram 



Sodium Chloride . . . .... 0.50 gram 



Calcium Sulphate . . 0.50 gram 



Magnesium Sulphate 0.50 gram 



Calcium Phosphate . 0.50 gram 



Ferric Chloride . . ... . 0.005 gram 



Distilled Water . . 1000.00 grama 



Add the ferric chloride at the time the solution is to be used, by adding a drop or 

 so to the solution in the bottle used for the seedlings. 



