VOL. IV.] Trees of Southei'n Calif 07'nia. 335 



canons are usually clothed with them. At about 3000 feet a 

 thin strip of dwarf pine {Pinus tuberculata) stretches for some 

 miles along the face of the range, bounded above and below by 

 the dense chaparral of Ceanothus and manzanita, which at this 

 altitude has replaced the Adenostoma of the lower slopes, and 

 is otherwise unbroken for another thousand feet. At 4000 feet 

 the spruce is displaced by the other coniferous trees which consti- 

 tute the main forest. Below 5000 feet this is mostly confined to 

 the northern slope of the range, but above that over- 

 flows to the southern side, and, indeed, below it on sheltered 

 slope-exposures. It is essentially a yellow pine {P. ponderosa) 

 belt, that being the prevailing species nearly to the tree limit; 

 with it are commingled, without any apparent vertical disposition, 

 many firs {Abies concolor) and Post Cedars, smaller numbers of 

 Black and Big-cone Pines {P. Jeffrey i lixi^ P. Coulteri), and still 

 fewer Sugar Pines, together with an abundance of Kellogg's 

 Oak, especially at the lower levels. This forest continues without 

 appreciable difference to about 11,000 feet on the sides of Gray- 

 back Mountain, where it begins to be intermixed with Pinus 

 coniorta, which in small isolated groups occurs in Bear Valley, 

 as low as 6000 feet. This in turn gives way at about 11,500 

 feet to PiiiKS albicaidis, which alone, forming the topmost belt, 

 reaches nearly to the summit, 11,725 feet above sea level.* On 

 the northern side of the rat-ge, which, it must be remembered, 

 is the one facing the desert and affected by its aridity, the spruce 

 re-appears at about 7000 feet altitude, but very sparingly, and 

 in small groups in sheltered and moist situations. At 6000 feet 

 Junipe?'i<s occidcnialis is mingled with the pines, and in one 

 place, mixed with Ccrcocarpiis Icdi/olius, forms a belt between 

 6000 and 7000 feet altitude. Beneath this, and separated from 

 it by an inter\al of chaparral, is a similar belt of Piiion Pines 

 {P. vionoph)l!a) between 4000 and 5000 feet, and connecting in 

 places with the upper edge of the Yucca belt. The Juniper and 

 the Piiion belts are about twelve miles long, their failure to 

 extend the whole length of the range being due to other causes 

 than elevation. 



* For most of my information concerning the Grayback forest I am 

 indebted to Mr. W. G. Wright, who has repeatedly explored that mountain. 



