250 Missouri Agricultural Report. 



60 per cent, of water, is twice as rich as cattle manure containing 

 80 per cent, of water. 



The information given above, based upon the records of chemi- 

 cal investigations, will enable one easily to understand and appre- 

 ciate the scientific and practical reasons for avoiding some methods 

 and for adopting other methods for handling farm manure. 



Average moderately fresh cattle or horse manure, made from 

 clover and timothy hay and some grain, with sufficient straw bed- 

 ding to absorb and retain the liquid manure, will contain per ton of 

 manure about 10 pounds of nitrogen, 2 pounds of phosphorous and 

 10 pounds of potassium, on the basis of 25 per cent of dry matter. 

 Computed at the present market values for these elements — 15 

 cents a pound for nitrogen, 12 cents for phosphorous and 6 cents 

 for potassium — such manure would be valued at $2.34 a ton. 



Some will argue that the plant food in farm manure is not so 

 readily available, and consequently should not be valued so highly 

 as that in commercial forms, but experiments show that when a 

 series of years is considered, the farm manure may be worth about 

 as much as the commercial materials on the basis of plant food 

 content. Thus, at the Rothamsted Experiment Station, an appli- 

 cation of 14 tons of farm manure, furnishing, according to the 

 above averages, about 140 pounds of nitrogen, 28 pounds of phos- 

 phorous and 140 pounds of potassium per acre per annum, has 

 maintained the yield of wheat at 35.6 bushels per acre, as an aver- 

 age of 50 years; while an average yield of 36.9 bushels has been 

 maintained during the same years by an application of commer- 

 cial plant food furnishing 129 pounds of nitrogen, 27 pounds of 

 phosphorous and 84 pounds of potassium per acre per annum. 



If we disregard potassium (which is not very important, be- 

 cause of the richness of Rothamsted soil in that element), the 

 amounts of plant food applied and the average yields produced 

 during half a century are not markedly diff'erent. The yield of 

 the fertilized plot averages 1.3 bushels higher during the fifty 

 years, but .7 bushel lower during the last ten years, than the ma- 

 nured plot. 



It is a very common and very erroneous belief that crop rota- 

 tion produces about the same effect as the application of farm 

 manure. 



The great difference between these two processes is that crop 

 rotation is a stimulant and ultimately reduces the fertility of the 

 soil to such a degree that the crops fail, especially the crops that 

 have the most stimulating effect, as clover; whereas, by the add!- 



