2 BULLETIN 426, U. S. DEPAETMEXT OE AGEICULTUEE= 



feet, about equally divided between private and Government owner- 

 ship. No reliable figures are available for Lower California, but the 

 amount there is known to be small. Within CaUfornia the best 

 available estimates indicate a stand of 39 bilhon feet, board measure, 

 about 24 billion on private lands and the remainder in Government 

 ownership within the National Forests. Of the three most valuable 

 widely distributed conifers within the State of California — redwood, 

 yellow pine, and sugar pine— though the sugar pine ranks third in 

 volume of stand, it is undoubtedly first in value of product. 



GEOGRAPHICAL AND COMMERCIAL RANGE. 



The geographical range of sugar pine extends from the valley of the 

 Santiam River, in the Cascade Range, in Marion County, Oreg., 

 through the Sierra and Coast Ranges of California to Mount San 

 Pedro, in the peninsula of Lower Cahfornia (PL I). Commercially, 

 however, the species is of importance only from Douglas County, 

 Oreg., to Kern County in the California Sierras, and Glenn County 

 in the California Coast Range. The largest trees and heaviest stands 

 within this area are found from Tulare to Eldorado Counties, Cal., 

 along the west slope of the Sierras. Nearly three-fourths of the 

 total stand is found in the Sierra Nevadas of CaUfornia and the bulk 

 of the remainder within that portion of the Coast Range which lies 

 north of San Fra,ncisco, Over one-half of the total is distributed 

 throughout the central Sierra region. It is seldom found in commer- 

 cial stands on the east side of this range south of Plumas County. 



ALTITUDE AND CLIMATE. 



The altitudinal range of merchantable stands of sugar pine extends 

 from 3,000 to 6,000 feet in the northern Sierras and from 5,000 to 

 9,000 in the southern Sierras, the southern coast range, and the 

 Sierra Madres. A few trees have been reported in the redwoods near 

 Cazadero, Sonoma County, Cal., at an elevation as low as 600 feet. 

 The extreme upper Hmit of the botanical range occurs on Mount San 

 Pedro, in Lower California, where the species has been reported at 

 ,11,000 feet. All gradations between these altitudes occur as the 

 latitude changes. 



In the sugar-pine belt the summers are hot and dry and the winters 

 moderately cold. Most of the stands are found between the annual 

 isotherms 44° and 60° F. Sugar pine occurs, however, in northern 

 Cahfornia, where the mean annual temj)erature is as low as 40°, and 

 in the southern part of the State, where it is as high as 70° F. It 

 endures average minimum monthly temperatures of 20° and average 

 maximium monthly temperatures of 97° F. 



Sugar pine is quite dependent upon atmospheric moisture. This 

 characteristic probabl}^ accounts, in large measure, for its hmited 



