FIELD CROPS. 



137 



Takings the averag-e composition of tlie crop for 4 years, tlie dry mat- 

 ter of the kernels grown on the unfertilized plat contained a smaller 

 percentage of all)nndnoids, fat, and ash, but a higher percentage of fiber 

 and nitrogen-free extract, than the grain grown with the aid of cow 

 manure, a deficiency of fertilizing materials having affected the quality 

 as well as the quantity of the crop. 



The following table sliows the difference in the amounts of nitrogen, 

 phosphoric acid, and i)otash supplied in manures and removed in the 

 crops, the plus sign indicating that the manures supplied more than 

 the crop.s removed and the minus sign that the manures afforded less 

 fertilizing material than the crops removed: 



Enrivhmeni or improvement of soil hij 6 years' manitrin(/ and cropping of corn. 



Cow manure. 



Nitrogen. 



' Pounds. 



After 5 years' cropping -|-494. 5 



Applied" in 1893 286. 3 



Taken nil' in crop of 1893 



Exces.s (-(-) or deflciencj- ( — ) after 6 

 year.s' cropping 



+ 70G. 



Pho.s- 

 phoric 

 acid. 



Pounds. 



-t-447.0 



' 136. 4 



al.6 



-1-561. 8 



Potash. 



Poiinds. 



+440.4 



204.5 



74.4 



-1-570. 5 



Hog manure. 



Nitrogen. 



Phos- 

 phoric 

 acid. 



Pota.'^h. 



Pounds. Pounds. 



+ 855.0 +1,766.4 



419.9 586.5 



61.7 22.9 



+1, 207. 8 



+2, 330. 



Pounds. 

 + 43. 4 

 72.4 

 47.3 



+ 68.5 



Fertilizer chemicals. 



Nitrogen. 



Phos- 

 phoi'ic 

 acid. 



Potash. 



No fertilizer. 



I Phos- 



Nitrogen.' phoric 



i acid. 



Potash. 



After 5 years' cropping 



Applied in 1893 



Taken off in crop of 1893 



Excess (-1 ) or deticieney (— ) after 6 

 years' cropping 



Pounds. 



+ 184.1 

 172.0 



Pounds. 



+ 536.7 



162.0 



15.4 



+300.9 +683.3 



Pounds. 



+95.9 



69.0 



35.5 



+ 129.4 



Pounds. 



—227. 1 



00.0 



29.8 



Pounds. 



+82.5 

 00.0 

 8.9 



-256.9 I H 73.6 



Pounds. 



—29. 3 



UO.O 



10.7 



—40.0 



Analyses of samples of soil taken October 6, 1891, give the amount of 

 nitrogen in the plats variously fertilized in the two preceding seasons: 



Nitrogen per acre in plats differently fertilized. 



The Dumas, Kjeldahl, and Jodlbauer-Kjeldahl methods of determin- 

 ing nitrogen were comj^ared, and the agreement of results was entirely 

 satisfactory to the chemist. 



Experiments on meadows made at the Pumpherston (Scotland) 

 Experiment Station, A. P. Aitken {Trati.^. Highhind and AfjI. ^Soc. 

 Scotland, 1894, pp. 385-409).— Seed of a mixture of grasses and clovers 



