1919] 



Pendleton : A Study of Soil Types 



405 



Table 17 — Eumus (and Humus Ash) 



Altamont Clay Loam 



Humus 



Horizons 



A Average B Average C Average 



Sample 



3 1.06 0.89 0.59 



1.13 1.09 0.84 0.86 0.58 0.59 



4 1.30 0.69 0.59 



1.33 1.31 0.71 0.70 0.2S 0.43 

 7 1.32 0.95 0.68 



1.31 1.32 0.96 0.96 0.68 0.68 



Average 1.24 0.84 0.57 



Humus ash 

 I [orizons 



Aver- 



A Average B Average C age 



% Vo % % 



1.29 1.08 0.95 



1.23 1.26 1.28 1.18 0.95 0.95 



0.80 0.98 0.91 



0.85 0.83 0.98 0.98 1.03 0.97 



0.72 0.87 1.09 



0.75 0.74 0.88 0.88 1.08 1.08 



0.94 1.01 1.00 



Table 18 — Humus (and Humus Ash) 

 San Joaquin Sandy Loam 



Loss on Ignition 



The loss on ignition of the A horizon varies directly with the tex- 

 ture of the soil, the heavier soils losing more on heating. Obviously 

 the water of combination of the clay is a large factor in this loss. In 

 the San Joaquin sandy loam the loss on ignition was determined in 

 the three horizons. In the other three types the A horizon was the 

 only one examined (tables 20, 21, and figs. 15-18). 



