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(1) Fertilizers on corn. — As in 18,SS, "in addition to the full amounts 

 of potash, phosphoric, acid, and nitioj>en {i. e. the amounts of each con- 

 tained in a crop yiehling- 30 bushels of grain peracre),smallerand larger 

 amounts of each were tested." The yields in 1888 and 1889 are tabu- 

 lated for each farm, as well as the averages for the three farms. 



A coniparisou of the results for the 2 years sliows that the fertilizers gave much 

 better returns at .Sp.artauburg and DarlingtoTi in 1889 than iu 1888> the increase of 

 yield in the former year amounting to from 75 to 100 per cent. * * * Applied 

 separately or combined in twos the fertilizers gave very poor returns. Potasli in 

 small or half doses was of some little benefit. The full amount of phosphoric acid 

 was called for but only half doses of nitrogen. Both constituents were of value to 

 the crop. 



Increasing the yield of any one or more of the constituents beyond a certain point 

 (the full or theoretical amount) gave no corresponding increase in the crop. From a 

 pecuniary standpoint but four of the api)lications gave profitable results. 



(2) Special nitrogen^ phosphoric acid, and potash experiments. — The 

 separate series of experiments to com])are the effects on corn of differ- 

 ent nitrogen, pliosphatic, and potash fertilizers, when each was used 

 in amounts furnishing the same quantity of nitrogen, phosjihoric acid, 

 or potash, respectively, were contimied in 1889 on all three farms. The 

 results in yield of corn and stover are fully tabulated for each series. The 

 indi(;ations from the 2 years' trials are given by the author as follows: 



[Nitrogen.] (1) The corn crop does not respond to lieavy applications of nitroge- 

 nous manures. Jloderateamoinits will jtrobably give fair returns. In our tests 120 

 pounds of nitratt^ of soda proved as ettective as 240 poun<ls; 168 pounds of dried 

 blood as effective as 32;") jjounds, etc. (2) Of the nitrogenous fertilizers commonly 

 used by our farmers (nitrate of soda, dried blood, cotton-seed meal, and cotton seed 

 whole or groun<l) one kind appears to be about as effective on Indian corn as 

 another, where e([uivalent amounts are applied. The employment of any kind should 

 therefore be determined l>y the cost of its nitrogen. * * * 



The results of the tests bear directly upon a question of great practical importance, 

 that of exchanging cotton seed for cottou-seed meal. Many mills offer 700 pounds 

 of meal, and some 1,000 pounds in exchange for 2,000 pounds of seed. Would such 

 exchange be judicious ? * * * It appears that as far as these tests go 560 pounds 

 of cottou-seed meal are fully equal in fertilizing value to 1,560 pounds of cotton seed, 

 a proportion of 1 to 2.79. In the oil mills a ton, or 2,000 pounds, of seed gives about 

 700 pounds of meal, besides oil and some waste product. Now 700 pounds is iu pro- 

 portion to 2,000 pounds as 1, to 2.85. This close correspondence of fertilizing value 

 to output is certainly remarkable. 



[Phosphoric acid.] The averages of the three farms for the 2 years show a 

 slight difference iu favor of the acid phosidiate. The reduced phosphate (containing 

 availal)le phosplioric acid) appears to stand next. The two basic phosphates — 

 Thomas slag and floats — gave about the same average. It appears also that in every 

 case the half amount of phosphoric acid gave nearly as good returns as the full 

 amount. The true results, however, were undoubtedly masked by the dry season of 

 1888, which prevented the action of the fertilizers at all three farms, and by their 

 fiiilure upon the thin, sandy soil af the Colinnbia farm botl^in 1888 and 1889. It 

 is very probable that iu favorable years the acid phosphate would show its superi- 

 ority, for the results thus fiir reached are iii favor of the soluble form. 



[Potash.] (1) It is doubtful whether potash was of any real benefit to the crop. 

 (2) It is certain that the full theoretical anu)unt deduced from the an.ilysis of the 

 plant was excessive, and that half this amount was abundantly sutiicient (perhaps 



