78 T. Lyttleton Lyon and James A. Bizzell 



Hart and Peterson (1911) estimate from figures given by Hall that 

 the annual loss of sulfur in drainage water from the Rothamsted soil is 

 from 20 to 80 pounds per acre, depending on the fertilizer treatment. 



The quantities of sulfur removed in drainage water for different periods 

 of time, as found by a number of investigators, are given in table 61. 

 The range of removal in these experiments is large, varying from about 

 8 pounds a year to about 280 pounds a year. The German experiments 

 show the greatest losses. In most cases, cropping the soils resulted in 

 a very considerable conservation of sulfur, amounting to more than 

 one might expect the crops to absorb. In the writers' experiments, 

 however, the crops used just about as much as the difference between 

 the drainage removal from the planted and the unplanted soil. The growth 

 of clover materially decreased the removal of sulfur in the drainage water, 

 presumably because of the large utilization of sulfur by that crop. 



REMOVAL OF PHOSPHORUS 



There has never been more than a trace of phosphorus in the drainage 

 water from any of these tanks. There are therefore no data to report 

 on phosphorus, except as to its removal in crops. The average amount 

 of phoephorus (P) removed annually from the soil by the crops produced 

 is shown in table 62: 



TABLE 62. Phosphorus in Crops 

 (Pounds per acre, annual average) 



The table shows that the tanks kept in grass most of the time (tanks 

 6 and 10) lost a much less amount of phosphorus in the crops than did 



7& 



