266 SOILS: PBOPEMTIES AND MANAGEMENT 



as plant-food. The quantity of nutrient elemen. t 

 annually from the average soil in a humid region ee 

 than equals that withdrawn by the crops. The results 

 from the Rothamsted drain gauges^ from 1871 to 1904 

 on a clay loam soil of three different depths are inter- 

 esting as to the light that they afford regarding actual 

 drainage losses : — 



January .... 

 February .... 



March 



April 



May 



June 



July 



August 



September . . . 

 October . . . . 

 November . . . . 

 December . . . . 



Mean total per year 

 Winter, October to 



March .... 

 Summer, April to 



September . . . 



Rain- 

 fall 



2.32 

 1.97 

 1.83 

 1.89 

 2.11 

 2.36 

 2.73 

 2.67 



3.20 

 2.86 



28.98 

 14.70 

 14.28 



Drain -^GE through 

 Soil 



Depth m Inches 



20 



1.42 

 0.87 

 0.50 

 0.49 

 0.63 

 0.69 

 0.62 

 0.88 

 1.85 

 2.11 

 2.02 



13.90 



10.09 



3.81 



40 



^.UO 



1.57 

 1.02 

 0.57 

 0.55 

 0.65 

 0.70 

 0.62 

 0.83 

 1,84 

 2.18 



.w.XO 



14.73 

 10.81 



3.92 



60 



1.96 

 1.48 

 0.95 

 0.53 

 0.50 

 0.62 

 0.65 

 0.58 

 0.76 

 1.68 

 2.04 

 2.04 



13.79 

 10.15 



3.64 



Propoktion or 



Rainfall Drained 



THROUGH Soil 



Per Cent 



20 



78.5 

 72.2 

 47.6 

 26.5 

 23.2 

 24.0 



23!2 

 35.0 



57.8 

 76.7 

 80.3 



48.2 

 68.6 



26.6 



40 



80 

 55 

 30 



26 

 27 

 25 

 23 

 32 

 57 

 76 

 85 



51.0 



72.8 





60 



48.0 



69.0 



25.4 



The rainfall and relative loss through the 40-inch depth 

 of soil is shown graphically in the following diagram : — 



^ Hall, A. D. The Book of tbe Rothamsted Experiments, 

 p. 23. London. 1905. 



