888 



(1) On the fertile soil ou which this experinicut is being conducted there is no 

 suftiiieut evidence as yet that phosphoric acid and potash are of auy benefit in a 

 fertilizer for corn, until combined with uitroj^en. 



(2) In 1890 and 1891 some increase has followed the nse of nitrogen in every case, 

 but in 1888 there is no evidence that nitrogen, whether used alone or iu combination 

 with phos])horic acid, has produced any increase of crop beyond the limits of proba- 

 ble variations in the soil itself, until we reach plats 17, 18. 20, and 21, and on these 

 l^lats tlie ap|>arcnt iuciease is insignificant when coin))ared with the great superi- 

 ority shown in tlie yield of the uulertilized platsof that season over that of the same 

 jihits in any subsequent season. 



The results are also rei^orted of experiments with fertilizers for eoru 

 on 5 i)rivate farms in as many counties. 



Tbe results are variable, but they agree upon two points; tlieseare: (1) Nitrate 

 of soda in combination with dissolved boneblack or muriate of potash, one or both, 

 has ])roduced an increase of crop in 46 nut of 48 trials, or jtractically iu every case; 

 (2) iu no case has the average increase of crop from this combination in any one of the 

 six series of experiments been sufficient to ))ay the cost of the fertilizer at present 

 prices of corn and fertilizers, resjiectively. 



The experiments justify the inference that then; may be excepticmal soils in Ohio, 

 upon which superphosjihate and jiotash without nitrogen will produce a larger 

 increase than they have shown in the average of these tests, but the evidence on this 

 point is not conclusive, and the fact that in 20 out of 4G trials iu which superphosphate 

 and potash were used without nitrogen there was no increase of crop, should lead the 

 farmer to exixTiment carefully before adojiting this system of partial fertilizing. 



E.rpvrlmcntH on oats (pi>. ol'-,"*,")). — The.se were on ~'2 plats and were in 

 continuation of the experiinent.s in 188U and 18!)(>, the plan of Avhich 

 was described in Bulletin vol. ill, No. 1 of the station (see Experiment 

 Station Kecord, vol. ii, j). 124). The yields are talnilated of ^rain and 

 straw on the i)lats in 1SS9, 18*J0, and 1891. and tlie increased yields with 

 fertilizers. 



" The fertilizers ai)i)arently ])roduced an increase of crop in i»ractii:ill>' 

 every case, the increase ln-ini; more uniform when the fertilizer con 

 tained nitrogen, lint at present prices of -^lain and fertilizers, respec 

 tively, the averajne increase has in no ease been sullicient to ]iay the 

 cost of the lertilizer." 



Fertili::trN on cnn)N (/loint in rotaiion (pp. ori-TiT). — To study the econ- 

 omy of fertilizers in a rotation of crops, 5 blo<'ksof 7 twentieth-a<re plats 

 each Avere used. Upon these blocks corn, oats, wheat, and a nnxture 

 of clover and timothy Ibllowed each other in the order named, the clovt-r 

 and the timothy oecui»yin,L; the land 2 years. The corn ami wheat croj)!* 

 ret'cived mixtures of .■>(>(» ])ounds of sui)erphosi>ates and 1(>() pounds of 

 muriate of ])t>tash, with and without 100 pounds of nitrate of soda 

 ]ier acre, ami 8 tons of bainyard manure per acre. The yields are 

 tabulated lor 181>1. 



Tiie experiments on cro))s grown in rotation have not yet been carried over a siitb- 

 cient lengtli of time to justify general conclnsions, l)nt thus far they otter no nuuf 

 encouragement to the use of chemical nuinnres than those on crops grown continu- 

 ously. 



A very wide ditVeniiee is indiciited in the value of stable manure according as it is 

 used flesh from tlie stabb- or alter half a year's leaching in the barnyard. Appar- 

 ently tiie margin of i»rofit in the use of open-yard manure is extremely meager. 



