56 FOREST TREES OF THE PACIFIC SLOPE. 



east of Chico, 8 miles east of Nelson, and to Palermo ; eastward to point 1 mile east of 

 Magalia (2,300 feet), West Branch Feather River, Yankee Hill, Harts Mill (1,700 feet; 

 7 miles east of Bidwell Bar). Yuba County: Westward to point 12 miles east of Marys- 

 ville : eastward to west hase of Oregon Hills. Nevada County: Eastward nearly to 

 Grass Valley and Nevada City. Placer County: Westward to Rocklin (22 miles north- 

 east of Sacramento) ; eastward to Colfax and considerably farther in canyon of North 

 Fork of American River. Sacramento County: Westward to Natoma (American River) 

 and Michigan Bar. Eldorado County: Eastward 3,000 feet to point 5 miles east of 

 1 lacerville. Pleasant Valley, canyons of North, Middle, and South Forks of Cosumnes 

 River and Mount Orcum. Amador County: Westward to point 1 mile east of Carbon- 

 dale; eastward to Oleta, Jackson Reservoir (1,900 feet), volcano basin (Sutter Creek), 

 and between volcano and Oleta. Calaveras County: Westward to point few miles east of 

 Wallace and some miles below Tuttletown and Angels ; eastward to Rich Gold Gulch. 

 Mountain Ranch. Mokelumne River at least to crossing between West Point and Defender, 

 to point 5 miles east of Murpheys (3.200 feet), and farther in canyon of North Fork 

 Stanislaus River. Tuolumne County: Westward to point 8 miles east of Cooperstown 

 (1,200 feet) : eastward to Cherokee Mine (east of Soulsbyville), Hetch-Hetchy Valley 

 (on main Tuolumne Riven, to 3,500 feet on Middle Fork of Tuolumne River. Mariposa 

 County: Westward to point 3 miles east of Merced Falls: eastward to point 5 miles east 

 of Coulterville (3,200 feet), to point 2 miles north of Cold Springs (Mariposa road), 

 to point on Merced River about 5 miles east of Mariposa, some distance east of Chow- 

 chilla at 3,100 feet, ridge near South Fork of North Fork San Joaquin River. Madera 

 County: Westward to point 2 miles west of Raymond (900 feet) and 16 miles east of 

 Madera (1,000 feet) ; eastward to point 3 miles northeast of Wassama (3.100 feet), 

 some miles east of Fresno Flat, at 3,000 feet, ridge east of North Fork, at 2.600 feet. 

 Fresno County: Westward to point 4 miles east of Pollasky, to Letcher, mouth of Mill 

 Creek, on Kings River about 20 miles east of Sanger ; eastward to Pine Ridge east of 

 Toll House, Big Creek, and Trimmer Springs (on Kings River). Distribution interrupted 

 in southern Sierras ; occurs in valley of Kern River from point 1 mile west of Walker 

 Pass to Kernville, at elevations of 2.500 to 5,000 feet ; southward to Walker Basin at 

 3,100 feet, and northward on Greenhorn Mountains, continuously into Tule Indian Res- 

 ervation. Abundant from Kings River northward, but absent from parts of Tule River 

 basin, from Kaweah basin, and from region between Kaweah and Kings rivers, but 

 reported in Eshom Valley. Kern County: Kernville to Havilah, Walker Basin, and nearly 

 to Caliente; east of Caliente on north slopes about li miles up Caliente Creek (1,400 

 feet), and to far beyond Piute post-office, going eastward to west edge of desert, here 

 meeting upper border of tree yuccas ; west of Caliente, on slopes of Bear Mountain ; 

 south of Caliente; common on slopes of Tehachapi Pass; encircles Tehachapi Basin, east 

 of Tehachapi, on hills between Tehachapi Basin and Mohave Desert; west of Tehachapi 

 Valley, on divides about Brite and Cummings valleys ; westward from west end of Cum- 

 mings Valley for about 12 miles to promontory overlooking Kern River plain. 



Reported northward in Coast Mountains to south slopes of Siskiyous, eastward to 

 Owens Valley, and southward to San Bernardino Mountains. 



OCCURRENCE. 



In "hot, dry valleys and on dry foothills. Grows thriftily on driest, shallow, coarse, 

 gravelly soils — often baked and cracking throughout rainless summer. Unaffected even 

 where brush is killed by drought. Nevertheless it grows rapidly and very thriftily 

 when planted in moist, rich soils within its range, where it becomes a much heavier 

 foliaged tree. 



Does not form forests, hut occurs mainly in open groups or widely scattered at lower 

 elevations, mostly with chaparral and foothill oaks ; higher up. less abundant and 

 mingled with scattered western yellow pine, which often extends below its main belt. 

 Best growth between 2,000 and 3,000 feet, where it is the only pine in chaparral. 



Climatic Conditions. — Not fully determined. Climate most suitable, apparently that 

 only of arid regions. 



Tolerance. — In early life endures shade, but does not require it. Seedlings come up 

 and grow rapidly under chaparral. In late life general appearance of tree indicates need 

 of. or adaptation to, the fullest light. 



Reproduction. — An annual seeder, but certain years cones are more abundant than 

 others. Germination only moderate, and vitality of seeds (out of cones) transient. 

 Large, heavy seeds scattered but little by wind, and falling mostly close to seed trees; 

 hence reproduction mainly near seed trees. Seeds germinate late in winter during rainy 

 season, usually under some shade and upon rough, bare mineral soil. 



