No. 4.] KEEPING UP FERTILITY. HI 



a laruer yield than broadcast in three experiments. Tliis 

 was upon land of moderate fertility. 



For croi)s in general, materials supplyins: from forty to 

 sixty pounds of nitroaeii, from forty to sixty pounds of 

 phosphoric acid and from sixty to a hundred pounds 

 of potash will generally give satisfactory results, provided a 

 system of rotation including some .legume is followed to 

 furnish a part of the nitrogen. If this is impracticable, con- 

 sideral)ly more of this element must l)e furnished. 



You have perhaps expected that I should give you formulae 

 for different crops. I do not consider it best to do this. I 

 do not know your soils, I am unfamiliar Avith your con- 

 ditions. If you shall desire to know what I have used, and 

 the results, I can tell you ; but I cannot promise equal 

 success to you. 



Just one more point, and I am done. If plant food is to 

 be purchased, my experience leads me to believe that 

 fertilizer will furnish it at less cost than manure. For six 

 years two plats of land have been continuously under the 

 same treatment on our grounds at Amherst. One has 

 received yearly nitrate of soda at the rate of one hundred 

 and sixty pounds ; dissolved bone-lilack, three hundred and 

 twenty pounds ; and muriate of potash, one hundred and 

 sixty pounds per acre. The other has received yearly five 

 cords of good manure. The crops in the order of succession 

 were : corn, corn, oats, grass, grass and corn. The increase 

 In crop due to the use of fertilizer has been worth $124.93 ; 

 the fertilizer has cost $68.40 for the six years. The increase 

 where the manure has been used has been worth $153.79; 

 the manure at five dollars per cord has cost $150. The 

 chief superiority for the manure has been in the grass crops, 

 •doubtless because of the more liberal supply of nitrogen. 

 In six years where the fertilizer has been used we have 

 applied one hundred and twenty pounds of nitrogen ; where 

 the manure has been used, we have applied not less than six 

 hundred pounds of nitrogen. The fertilizer could have been 

 made to make a much better yield of grass by the use of 

 more nitrogen. 



On the college farm I have for five years been comparing 

 Tarious mixtures of fertilizers with manure for grass. The 



