150 



LESSONS IN AGRICULTURE 



pastures, fields and gardens, as we shall learn in this 

 lesson. 



Important elements of the soil. As was suggested 

 in the last lesson, the three elements likely to be lack- 

 ing in our soils are nitrogen, phosphorus, and potash. 

 The fertilizers we use must, therefore, contain these 

 essential elements. The crop will usually tell the farmer 

 by its appearance the kind of food it most needs. Good, 



FIG. 46. WASTE OF MANURE 



fertile, well-drained soil, properly cultivated, usually 

 produces healthy, dark green plants with strong, good- 

 sized stalks, and numerous, well-filled seeds. 



Nitrogen. The growth of the stalks and foliage of 

 the plant is largely due to the nitrogen, providing the 

 heat, light, air, and moisture conditions are favorable. 

 If the plant has a yellow, sickly appearance, and under 

 cultivation refuses to grow, it is likely starving for 

 want of nitrogen. The best fertilizer, and the one nearly 

 always giving best results, is barnyard manure. It has 

 right amounts of nitrogen, phosphoric acid, and potash, 

 in forms readily available to the plant. Especially 



