FOREST TEEES OF THE PACIFIC SLOPE. 317 



but in Stanislaus National Forest ranging between 1,500 and 6,500 feet. Locally noted 

 in Yosemite Valley, at 4,000- feet, in pure growth west of Camptonville, in Yuba County, 

 and vicinity of Lake Taboe. In southern Sierras, generally at 4,500 to 7,000 feet, 

 where it occurs as follows: North Fork of Kings River ; Bubbs Creek (head tributary 

 South Fork Kings i up to Bubbs Dome; Frazier Mountain; East Fork of Kaweah River, 

 at 4,900 to 7,200 feet, from Bigtree Canyon to point about 4 miles below Mineral King ; 

 White River (Tulare County) ; on crests and west slopes of Greenhorn Mountains (in 

 T. 20 S., R. 30 and 31 E.), at 5,900 and 4,750 feet, and on Little Posey Creek, at 4,700 

 feet, in depression between east and west ridges of these mountains (Kern County). 

 On east slope of Sierras, at Independence. Very abundant on southern terminal ranges 

 of Sierras, as on Mount Breckenridge, above 4,000 feet, and probably also on Piute 

 Mountain. Not reported from Tehachapi Mountains. In northern coast ranges, com- 

 mon in Trinity National Forest eastward to between Lewiston and Weaverville (west 

 border of Sacramento Valley) : locally noted on Grouse Creek Canyon near South Fork 

 Mountain, at 2,300 and 2.500 feet. Southward in Stony Creek National Forest, very 

 abundant in yellow pine belt at 3,000 to 6,000 feet, particularly in western part of 

 forest on headwaters of Eel River. In vicinity of Bay, only on higher summits, such 

 as south slope of Mount St. Helena, north base of Mount Tamalpais, upper San Pablo 

 Creek, and east side of westmost coast range of Santa Clara Valley ; not on Berkeley 

 nor Oakland hills. Plentiful in southern coast ranges, especially in Santa Lucia Moun- 

 tains of central and northern parts of Monterey National Forest, where, on both sides 

 of range, it occurs at 2,000 to 5,000 feet elevation in Sur, Carmelo, and Arroyo Seco 

 river basins. Not common in Santa Barbara National Forest, but widely distributed at 

 3,500 to 6.200 feet in watersheds of Santa Maria. Matilija, I'iru-Sespe, and Elizabeth 

 rivers, being abundant on Fine Mountain and in pure stands on summit of Liebre Moun- 

 tain. Range in San Gabriel Mountains not fully recorded, but probably not there to any 

 extent. Common in pine belt of San Bernardino Mountains ; here locally noted near 

 head of Waterman Canyon at 3.000 feet — a low altitude ; on City Creek road off Plunge 

 Creek, at 4,400 feet, and in Little Bear Valley, at 5,000 feet. Very common in pine 

 belt of San Jacinto Mountains on west and south sides, at 5,000 to 9,000 feet ; also in 

 Strawberry Valley, at 5.200 feet; rare in Tahqultz Valley, and not detected on north side 

 of mountains. Southward, the most prominent oak in Palomar Mountains, forming nearly 

 half of the mixed stand on upper slopes, but in Cuyamaca Mountains less abundant 

 than Qucrciis ay ri folia ; locally noted in this region on south side of Smiths Mountain 

 at 4,100 feet, and at Campbells ranch (Laguna Mountains), at 5,490 feet. Reported 

 from Hanson Laguna Mountains of northern Lower California at elevations above 

 4,000 feet. 



OCCURRENCE. 



On mountain slopes, benches, valleys, in canyon bottoms and lower sides, and on 

 upper foothill slopes; in dry gravelly and sandy soils, or in very rocky places with 

 scanty soil. 



Forms pure, open groves and limited stands, or mingles (at lower levels) with gray 

 pine, Douglas fir (Oregon), California laurel, western dogwood, canyon live oak, and 

 Straggling western yellow pine. Higher up. commonly with latter pine, incense cedar, 

 and occasionally with bigtree. Largest in yellow-pine belt on sheltered benches, valleys, 

 and coves, and smallest on exposed high slopes. 



Climatic Conditions. — Not fully determined, but mainly like those of western yellow 

 pine. 



Tolerance. — Endures moderate shade in early life, but requires full overhead light 

 for good growth later. In mixture with yellow pine, subordinate. 



REPRODUCTION. — Abundant periodic seeder at 2 to :; year intervals, but locally some 

 seed is borne nearly every year. Germination scanty ; best in slight shade on exposed 

 mineral or humus. 



Tanbark Oak. 

 Querents " densiflora Hooker and Arnott. 



DISTINGUISHING CHARACTERISTICS. 



Tanbark oak is widely known in its range by this name on account of the 

 extensive use of its bark for tanning on the Pacific <"<>ast. where it is as impor- 

 tant in the leather industry as chestnut oak (Quercus prinus) is in the East. 



"Although never known to lay people as anything but an oak, for which the technical 

 name Quenus stands, this tree has characters in its reproductive organs which techni- 

 cally permit its separation from all other oaks of the genus Qucrcus into another 

 15188—08 21 



