292 FOREST TEEES OF THE PACIFIC SLOPE. 



are matured in one season, and when ripe are dark to light chestnut-brown ; 

 cups externally clear red-brown and minutely hairy; their scales, especially 

 those at the bottom, having a thick, ridge-like projection on the back and sharp, 

 hairy points. 



Wood very dark brown, exceedingly heavy, dense, stiff, and brittle ; green 

 wood checks and warps badly when exposed. It has nothing to recommend it 

 for commercial purposes, but locally it is likely to be of some importance for 

 fuel, of which it furnishes a good quality. It is a useful desert species, and 

 owing to the limited number of trees and their restricted range, attention should 

 be given to its reproduction and extension. 



Longevity. — Not fully determined. Judged to be moderately long-lived. One 

 tree 14^ inches ( inside of bark) showed an age of only 3S years. This indicates 

 rapid growth for a desert oak. 



RANGE. 



Southern California and northern Lower California. 



California. — Low hills in coast regions of southern part from Sierra Madre, where It 

 extends from Altadena to Glendora, southward in a belt about 50 miles wide, beginning 

 15 to 20 miles from sea. to mesa east of San Diego. Forms about one-third of the 

 stand in Falomar Mountains and is second in abundance to Quercus califomwa. Rare 

 in Cuyamaca Mountains. At Mexican line extends from Campo to Tecate Mountain, 2T 

 miles from coast. 



Lower California. — Extends only a short distance from north boundary. 



OCCURRENCE. 



Low hill slopes and dry, rolling mesas, in loamy sand and gravel soils. Forms small 

 groups and open pure patches, but usually in mixture with California live oak. Climatic 

 conditions, silvical characteristics, and reproduction undetermined. 



California Scrub Oak. 



Quercus dumosa Nuttall. 



DISTINGUISHING CHARACTERISTICS. 



With the possible exception of the polymorphous Qurrcus undulata, of Rocky 

 Mountain range, California scrub oak unquestionably varies more than all 

 other oaks in the form and size of its leaves and acorns. No sort of satisfactory 

 harmony can be established between the perplexing phases of its development, 

 and one is likely to be hopelessly confused without a most comprehensive field 

 study of the bushes and small trees belonging to this species. At least 3 species 

 and as many varieties have been singled out. but the distinctions between them 

 are hopelessly confused by the occasional occurrence of their various types of 

 leaf and fruit on the branches of a single individual. Unless the observer has 

 a comprehensive view of all the points that seem to compel the uniting of 

 these diverging forms into one variable species, and one fairly constant sub- 

 species, this reduction may seem hardly proper. 



It is known as " scrub oak." for it occurs in the main, singly or massed in 

 low thickets, with the fine, exceedingly stiff twigs and branches closely mingled. 

 The California coast island representatives grown in sheltered places are from 

 20 to 25 feet high and from S to 12 or more inches in diameter, with scaly brown 

 bark; while the bark of the scrub forms is scaly and light ashy-gray. The 

 twigs, so rigid as to seem thorny to one penetrating a thicket, are branched at 

 very abrupt angles. No adequate statement can be made of the size or form 

 characters of the leaves and acorns, types of which are figured as fully as pos 

 sible in fig. 131. 



