1914] Loughridge: Hu7nus and Nitrogen in Calif ornia Soil Columns 229 



but the rest of the valley has sandy and sandy loam soils, with 

 some heavier clays on the south. 



Two columns were obtained by ]\Ir. F. E. Johnson — one from 

 the sandy lands about one-half mile north of Fernando and 

 representing the "granitic wash land" at the foot of the hills; 

 the other from lowland near the old Mission two miles west of 

 Fernando. 



The two soils from the San Fernando Valley are quite differ- 

 ent in their percentages of clay as well as in amounts of humus 

 in the first foot, in the upper three feet, and in the entire column, 

 the advantage being with the soil from near San Fernando. The 

 Mission soil is more sandy because of the wash from the hills. 

 While the humus of the ^Mission column is the richer in nitrogen, 

 the two are equal so far as the soil is concerned and are much 

 below the requirements for fertility. 



The soil from San Fernando probably is similar in character 

 to that of the large olive orchard at Sylmar, a few miles north 

 near the foot of the hills. 



Table 30. — Humus 



Sum of per cents 5.56 

 Average per foot .46 



Upper 3 feet : * 

 Sum of per cents 2.08 

 Average per foot .69 



IX Soil Columns of Sax Gabriel 

 Los Axgeles County 



COV'IXA 



Humus- 

 Xitrogen in Soil 



, -^- V Clay 6.84 



Humus Soil Humus 



3.82 .04 Sandy loam.. .58 



3.77 .02 Sandy loam.. .48 



3.75 .02 Sandy loam.. .46 



3.54 .02 Sandy loam.. .32 



3.59 .02 Sandy loam.. .30 



3.13 .02 Sandy loam.. .26 



3.24 .01 Sandy loam.. .24 



3.07 .01 Sandy 18 



2.86 .01 Sandy 16 



2.67 .01 Sandy 18 



2.50 .01 Gravelly 18 



2.86 .01 Coarse gravel 



3.34 



3.24 .02 .28 



Valley, 



3.78 .03 



1.51 

 .50 



4.75 .02 



4.55 .02 



* Range of most annual plant roots. 



