120 NATUEE AND PROPERTIES OF SOILS 



63. Tlie htinnis content of soils is of course lower than 

 the organic matter contained in them. It likewise varies 

 according to climate and region, not only in amount, but also 

 in composition. The following data from Hilgard^ and 

 Alway ^ illustrate these points : 



Table XXVI 



the compositiolsr of california arid and humid soils. 



(hilgabd) 



Desckiption 



Humus in 

 Soil 



(Percentage) 



Nitrogen in 

 Humus 



(Percentage) 



Nitrogen in 

 Soil 



(Percentage) 



41 Arid uplands soils 



15 Sub irrigated arid soils. . 

 24 Humid soils 



.91 

 1.06 



4.58 



15.23 

 8.38 

 4.23 



.135 

 .099 

 .166 







Table XXVII 



COMPARATIVE COMPOSITION OF SEMI-ARID (wAXJNETA) AND HUMID 

 (weeping water) loess soils of NEBRASKA. (ALWAY) 



Depth 



Oeganio Matter 

 (Percentage) 



HtlMTJS 



(Percentage) 



Nitrogen 

 (Percentage) 





Watjneta 



Weeping 

 Watee 



Wauneta 



Weeping 

 Wateb 



Wauneta 



Weeping 

 Wateb 



1st foot. 

 2nd " . . 

 3rd ".. 

 4th "... 

 5tli "... 

 6th ".. 



2.77 



1.38 



1.09 



.79 



.55 



.45 



4.98 



3.02 



1.38 



.83 



.45 



.36 



1.02 

 .65 

 .48 

 .34 

 .26 

 .26 



2.34 

 1.29 

 .55 

 .27 

 .23 

 .19 



.136 

 .082 

 .065 

 .046 

 .038 

 .030 



.236 

 .154 

 .083 

 .059 

 .043 

 .038 



^Hilgard, E. W., Soils, pp. 136-137; New York, 1911. For further 

 data regarding Hilgard's conclusions see: Alway, F. J., and Bishop, 

 E. S., Nitroge% Content of the Humus of And Soils; Jour. Agr. Ees., 

 Vol. 5, No. 20, pp. 909-916, Feb., 1916. 



^ Alway, F. J., et al,, The Loess Soils of the Nehraslca Portion of the 

 Transition Megion; J. Eygroscopictty, Nitrogen and Or game Carton; 

 Soil Sci., Vol. I, No. 3, pp. 197-238, Mar., 1916. U. Humus, Humus-N'b- 

 trogen and Color; Soil Sci., Vol. I, No. 3, pp. 239-258, Mar., 1916. 



