332 Bulletin 241. 



ten plats receiving precisely the same application of commercial fertilizer 

 as in the year 1905, was at the rate of 2391.1' pounds per acre or 39 per 

 cent greater. While the actual increase was thus greater in 1906, the 

 percentage increase, when compared with the yield of the plats receiving 

 no treatment considered as 100, was generally less (See tahle p. ). 



There are two possible explanations for this result. The greater 

 increase in yield may have been due to the more favorable season for the 

 growth of timothy, making it possible for the plants to make greater use 

 of the fertilizers applied, or the application of the previous year may have 

 had a residual effect, either in the way of plant food actually carried 

 over, or b}- producing more vigorous plants. It is fair to assume that a 

 vigorous plant will stool more abundantly, and that the new plants thus 

 produced will be more vigorous than those from less vigorous plants, if 

 the better environment is maintained. Thus, the number and vigor of 

 plants may be increased upon the plats receiving fertilizers as compared 

 with those which did not have such treatment. Whether in this case 

 the greater increase in yield, when fertilizers were applied in 1906, as 

 compared with 1905, was due to the previous application of the fertilizer 

 or to better seasonal conditions in 1906, must be left for further study, 

 but it seems not unlikely that both may have been factors in the results 

 obtained. 



Results with Fertilizers Stated in Terms of Money 



In 1906, in every case the increase in hay was worth more than the 

 cost of the fertilizer applied. The value of the increase over the cost of 

 the fertilizer applied, varied from 61 cents per acre, when acid phosphate 

 only was applied in the spring of 1906, to $26.54 per acre, when 20 tons 

 of manure had been applied in the fall of 1903. The cost of the fer- 

 tilizers applied to. the oat crop raised in 1904 was in every instance 

 greater than the value of the increase. Starting with this handicap, the 

 cost of the fertilizers applied during the three years, has been less than the 

 value of the increase in the three crops with the exception of the plats 

 where acid phosphate alone was applied, or an excessive proportion of 

 acid phosphate was applied. Aside from the stable manure, the largest 

 net gain from the application' of fertilizers was where- 320 potmds of 

 nitrate of soda, 320 pounds of acid phosphate and 80 pounds of muriate 

 of potash were applied. The reader should be careful to observe that ^le 

 net gain is not necessarily the new profit obtained from the application of 

 the fertilizers. The net gain or net loss is merely the difference between 

 the value of the crop produced, based upon the December farm price of 

 the product for an average of ten years and the cost of the fertilizer at 

 the valuation placed upon them in Bulletin 2t,2, p. 3. It is entirely prob- 



