46 " MANUAL OF GENERAL AGRICULTURE. 



No. 1. No fertilizer, serving as a check. 



No. 2. 10 Ibs. sulphate of potash. (Approximate 

 cost 4c per Ib.) 



No. 3. 20 Ibs. acid phosphate. (l%c per Ib.) 



No. 4. 10 Ibs. nitrate of soda, .(3c per Ib.) 



No. 5. 10 Ibs. nitrate of soda, 20 Ibs. acid phosphate. 



No. 6. 10 Ibs nitrate of soda, 10 Ibs. sulphate of pot- 

 ash. 



No. 7. 10 Ibs. sulphate of potash, 20 Ibs. acid phos- 

 phate. 



No. 8. 10 Ibs. nitrate of soda, 10 Ibs. sulphate of 

 potash, 20 Ibs. acid phosphate. 



No. 9. A half ton of stable manure. 



No. 10. Special. Some fertilizer not included in the 

 above but used locally as 2 Ibs. land plaster (gypsum, or 

 cow manure, or sheep manure, etc.) Plaster and manure 

 show more marked results the second year. 



Sow all plats exactly alike with the same kind of 

 seed. One of the crops ordinarily raised in the commun- 

 ity, such as corn, wheat, barley, etc., should be used. If 

 the class is large enough three or four set of plats as de- 

 scribed above may be used, each being sowed to a differ- 

 ent crop. When the crop is ripe, each plat should be 

 separately cut and threshed and the yield of grain and 

 straw both carefully weighed. A study of the yields of 

 the plats as compared with the fertilizers applied will give 

 the necessary data to determine what combination of fer- 

 tilizing material will cause the field to increase its yield 

 of that particular crop, and will give a partial check on 

 the deficiency of the soil in any particular plant food. A 

 second year of tests on the same plats will serve as a val- 

 uable check on the first year's results. 



Let the students devise a series of tests to show the 

 fertilizer requirements of the fruit trees in some nearby 

 orchard. Fertilizers should not be applied around the 

 base of the tree or much injury may be done. The feeding 

 roots are spread over an area equal to or greater than that 

 covered by the branches, and the fertilizer should be 



