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



eentage of nitrogen in the soil is fair, especially in the first foot. 

 The loam soil from Irvine is not so well supplied with humus 

 and nitrogen as could be desired. 



Interior Valleys 



The immediate coast line is bordered by a wide mesa which 

 extends south to the state line, interrupted by the characteristic 

 deep and narrow valleys or occasional streams. The valley of 

 the San Diego River is wide and affords much land for culture 

 purposes. The mesa reaches eastward in width to the foot of the 

 higher rolling hills, which rise still higher into the San Jacinto 

 IMountains. Among these hills lie numerous valleys, small and 

 large, whose soils are rich and productive. 



Fallbrook Mesa. — The hills are for the most part somewhat 

 rolling and capable of cultivation whenever the soil is of sufficient 

 depth and extent. Fallbrook affords an example of these cultiv- 

 able hills and a column of the soil was taken from the hillside 

 vineyard of Loma Ranch south of the town. The red clay loam 

 soil was of varying thickness and imderlaid by a mass of dis- 

 integrated granite. 



Ferris Valley lies southeast of Riverside at the western foot 

 of the San Jacinto Mountains. It is about ten miles long and 

 six wide, and has a variety of soils, as described by Professor 

 Hilgard in the Annual Report of the Agricultural Experiment 

 Station for 1894-95. The heavier soil from the center of the 

 valley, about a mile east of the town of Ferris, was selected and 

 a column taken by Mr. F. E. Johnson. 



The Valley of Escondddo is a large and productive valley 

 lying near the mountains. Its soil is a loam. A column was 

 taken to a depth of twelve feet by ^Ir. F. E. Johnson in the 

 vineyard of C. C. Katzenburger on the north side of the valley. 



El Cajon Valley lies among the high mountains twenty-nine 

 miles east of San Diego and has an area of six by four miles. 

 The land is a reddish sandy loam and is very productive. A 

 column twelve feet in depth was taken from near the cross- 

 roads by Mr. F. E. Johnson. 



