LOSSES OF MOISTURE AND PLANT FOOD BY PERCOLATION. 5.1 



4. Sulphate of potash increased percolation through the sandy soils 

 but decreased percolation through the clay soils. 



5. Application of manure increased percolation from the sandy soils 

 especially. The fall application of manure was more effective than the 

 spring application. 



6. The nitrates in the water percolating from the uncultivated soils 

 is related to a certain extent to the total nitrogen of soil and subsoil. 



7. More nitrates appeared in the percolates from manure applied 

 October 15 than from that applied March 15. On an average, 53.7 

 per cent, of the nitrogen was thus changed. The nitrates produced 

 from 9 tons of manure per year were sufficient for about 20 bushels 

 of corn. 



8. An application of nitrate of soda gave an increase in the nitrates 

 in the succeeding percolates of two of the soils, but, with the other six 

 soils, no effect was observed until three or four weeks later. 



9. Only small quantities of potash appeared in the percolates from 

 most of the soils, even after heavy applications of potash were made. In 

 three years, the maximum loss was 12 per cent, with the -Norfolk sand, 

 and from to 4.5 per cent, with the other soils. 



10. From 9.7 to 66.6 pounds per acre per year of potash were lost 

 by percolation from the uncropped, uncultivated soils. Losses from 

 cropped soils would, of course, be much less. The losses are to a cer- 

 tain extent related to the active potash of the soil. 



11. Losses of phosphoric acid in the percolates was very small. 



12. Losses of lime from the uncropped, uncultivated soils vary from 

 70 to 582 pounds per acre and is, in a general way, related to the quan- 

 tity of lime soluble in strong hydrochloric acid. 



The conclusions given above may be modified or supplemented by 

 related work carried on at the same time, in which the soils were 

 weighed, and which has not yet been digested for publication. 



