162. QUERCUS CALIFORNICA CALIFORNIA BLACK OAK. 39 



stout peduncles about in. in length; nut oblong or obovate, -J to 1| in. long; 

 puberulous at least at the apex, light chestnut-brown and often longitudinal stri- 

 ated, shell thin, tomentose inside, cup generally about one half or less covering the 

 nut (but exceptionally nearly enveloping it), puberulous inside and composed of 

 thin ovate-lanceolate light brown scales with membranous eroded margins. 



The Black Oak of California occasionally attains the height of 100 

 ft. (30 m.) with a trunk 3 or 4 ft. (1 m.) in diameter, clothed in a 

 dark reddish-brown or blackish bark (whence the name Black Oak) 

 checked into small and firm scales or on the largest trunks into broad 

 longitudinal scaly ridges and plates. 



HABITAT. Among the coast ranges from the vicinity of Eugene 

 Oregon southward a little distance back from the coast and on the 

 western slopes of the Sierra Nevada Mountains to near the southern 

 boundary of California, growing in elevated valleys and on slopes to 

 the altitude of about 8,000 ft. It is especially abundant and vigorous 

 to the northward in its range, and at about 6,000 ft. elevation on the 

 mountains. 



PHYSICAL PROPERTIES. Wood heavy, hard, strong but rather 

 brittle, with numerous but comparatively small medullary rays and 

 numerous large open ducts marking the annual rings, of a pinkish- 

 brown color with buff-white sap wood. Specific Gravity, 0.6435; 

 Percentage of Ash, 0.26; Relative Approximate Fuel Value, 

 0.6418; Coefficient of Elasticity, 74488; Modulus of Rupture, 768; 

 Resistance to Longitudinal Pressure, 449; Resistance to Indenta- 

 tion, 174; Weight of a Cubic Foot in Pounds, 40.10. 



USES. -The wood of the Black Oak is used to some extent for 

 fuel, and its ornamental value would suggest its usefulness for interior 

 finishing, etc., though we understand it is not much used. The bark, 

 which is quite rich in tannin, is used to some extent for tanning pur- 

 poses and is said to be of about double the value of Hemlock bark for 

 that purpose. 



MEDICINAL PROPERTIES are not recorded of this species, but doubt- 

 less the tannin of the bark would be of value where an astringent 

 action is required. 



ORDER BBTULAOEJE: BIRCH FAMILY. 



Leaves simple, alternate, straight-veined and furnished with stipules which 

 fall away early. Flowers mostly naked, monoecious, both kinds in catkins 2 or 3 

 together under a 3-lobed bract or scale. Sterile flowers with distinct stamens 

 and 2-celled anthers. Fertile flowers with two thread-like stigmas, and a 2 celled 

 ovarv. each cell containing 2 pendulous ovules, becoming by abortion in Fruit, a 

 small, 1 -celled, 1 -seeded nutlet, often with membranous wings; seed anatropous, 

 albumenless, with flattish, oblong cotyledons which become foliaceous in 

 germination. 



Trees or shrubs, with bark which separates more or less easily into thin layers. 



