112 AGRONOMY 



PRACTICAL EXERCISES 



1. Make an expedition to the fields and woods for evidences of 

 "fairy rings." 



2. In the experiment garden make a test of the soil as directed on 

 page 104. 



3. Make a collection of all of the commercial fertilizers. Label. 



4. Make a list of all the legumes, cultivated or wild, that can be 

 found in the school garden. 



5. Make a list of the wild legumes of the region. 



6. Make up an extract of rich soil by soaking it in water. Put a 

 drop of the turbid water on a slide and examine with the high power of 

 the microscope for the bacteria. 



7. Dig up clover or other legumes and look for the nodules on their 

 roots. 



8. Crush a nodule and examine it under the microscope. 



9. What is the limiting factor of plant growth in your region? 



References 



Hopkins, " Soil Fertility and Permanent Agriculture." 



Roberts, "The Fertility of the Land." 



Voorhees, "Fertilizers." 



Warren, " Elements of Agriculture." 



Farmers' Bulletins 



16. Leguminous Plants. 



31. Alfalfa or Lucerne. 



44. Commercial Fertilizers. 



77. The Liming of Soils. 



89. Cowpeas. 

 123. Red Clover Seed. 

 144. Rotation of Crops. 

 192. Barnyard Manure. 

 237. Lime and Clover. 

 245. Renovation of Worn-out Soils. 

 278. Leguminous Crops for Green Manuring. 



Bureau of Plant Industry 



71. Soil Inoculation for Legumes. 

 173. Seasonal Nitrification as influenced by Crops and Tillage. 



