250 University of California Publications in Agricultural Sciences [Vol. 1 



GENERAL SUMMARY 



INDIVIDUAL SOIL COLUMNS HAVING THE HIGHEST 



HUMUS CONTENT 



In looking over the 109 columns of soil taken from the various 

 agricultural regions of the state, we find that eighteen have each 

 more than 2 per cent of humus in the surface foot, and thirty- 

 two others have more than 1 per cent, the remaining fifty-nine 

 having less than that. 



The following twenty-five localities are worthy of special 

 mention, for in their respective columns more than 1 per cent 

 of humus is found in each individual soil layer to depths of 

 three to seven and even nine feet below the surface; they are 

 ranged according to depth. 



Table 43. — Columns with 1 per cent of Humus in Three or More 



Individual Feet 



Soil Locality County Depth 



Tule Stockton San Joaquin 9 ft. 



Loam Arroyo Grande A'alley San Luis Obispo 7 ft. 



Loam Arroyo Grande Seed-farm ....San Luis Obispo 7 ft. 



Clay loam Lompoe Seed-farm Santa Barbara 7 ft. 



Loam ^Santa Eosa Sonoma 6 ft. 



Adobe Berkeley Alameda 6 ft. 



Loam Russian Eiver Sonoma 5 ft. 



Clay loam Walnut Creek Contra Costa 5 ft. 



Adobe El Verano Sonoma 4 ft. 



Loam *Yountville Napa 4 ft. 



Clay Gilroy Santa Clara 4 ft. 



Loam Chino San Bernardino 4 ft. 



Loam Klamath (tule) Siskiyou 4 ft. 



Loam Glenn Glenn 3 ft. 



Sandy Chico Butte 3 ft. 



Clay loam Davis Yolo 3 ft. 



Clay Farmington San Joaquin 3 ft. 



Loam Newcastle Placer 3 ft. 



Loam Kenwood Sonoma 3 ft. 



Adobe San Ramon Contra Costa 3 ft. 



Clay Santa Clara Seed-farm Santa Clara 3 ft. 



Loam Pomona Cienega Los Angeles 3 ft. 



Clay Santa Ana Orange 3 ft. 



Clay Alturas meadow Modoc 3 ft. 



Loam Cedarville Modoc 3 ft. 



