334 Trees of Southern California. [ZOE 
broken are the mountains in many parts, and so invaded and 
intersected are the wooded tracts by chaparral. Compared with 
the great forests at the north these are not only insignificant in 
extent, but are equally unable to sustain the comparison in the 
size of the trees, or the density of their growth. Scattered in 
loose array over the hillsides, it is only on the moister soil of the 
flats, or in the shelter of cafions that the trees cast a dense 
_ shade, or attain to lofty proportions; yet they do not lack the 
extent and magnitude to excite those feelings of admiration and 
exaltation which forests ever raise in the mind, while their park- 
like disposition and the variety of species free them from gloom 
and monotony. 
THE SAN BERNARDINO FOREST. 
The outline of the area occupied by the largest, or the San 
Bernardino forest is that of a wedge, the point near the Cajon 
Pass, broadening eastward to Grayback Mountain; the length 
being about forty miles, and the greatest breadth twenty miles, 
the district included being in part forest, and in part chaparral or 
barren rock. On the south from a valley base of about 1200 feet 
above sea level the mountains rise with great abruptness to a 
crest of from 4000 to 8000 feet altitude, which runs in a generally 
east and west direction. The northern slope of this ridge, less 
abrupt than the southern, constitutes the water shed of the Mojave 
River, and on it is located the largest and best, as well as the 
most accessible body of timber. This is nearly twenty miles in 
length, and from one to three miles in breadth, South and east 
of this axis, and separated from it by the gorge of the Santa Ana 
River, which receives their drainage, rise the twin peaks of San 
Bernardino and Grayback. is region is of an exceedingly 
rugged character, and the forests which it nourishes are broken 
and difficult of access. 
Commencing now at the southern foot of the range, a few 
small spruce (Pseudotsuga macrocarpa) are found on sheltered 
western or northern exposures, along the cafions, at about 
2500 feet altitude;* these increase in size and in abundance 
until at between 3000 and 4o00 feet altitude both sides of the 
* On East Twin Creek, below the Arrowhead Hot Springs, a few grow as 
low as 1700 feet altitude. 
