138. QUERCUS DENSIFLORA TAN-BARK OAK. 3 ( J 



with broad rounded top of many branches, sometimes of very wide ex- 

 panse and often very much resembling large apple trees in habit of 

 growth. Indeed, as one passes through a region where the tree is com- 

 mon, and growing as it often does sparsely scattered over the country, 

 at some distance apart, the thought constantly recurs to him what a 

 splendid lot of large apple trees. 



The persistence of the leaves, though properly evergreen, is quite vari- 

 able, some trees losing nearly or quite all of the leaves during the winter, 

 and others retaining them apparently intact. The bark of trunk is thick, 

 reddish and spongy within, of a dark-gray color outside, and fissured into 

 broad, large, firmly adherent, longitudinal ridges, the smooth gray epi- 

 dermis of the young tree long persisting on the centers of the ridges of 

 the old bark. It is very similar in its appearance to the bark of the 

 Rock Chestnut Oak (Q. Prinus) of the Eastern States. 



HABITAT. California, in the vicinity of the coast, from Mendocino 

 County southward to Lower California, especially abundant and well- 

 developed southward and on Santa Cruz Island. 



PHYSICAL PROPERTIES. Wood heavy, hard, compact, rather brittle, 

 the annual layers of growth not all easy distinguishable, with thick con- 

 spicuous medullary rays, between and parallel with which are open ducts 

 arranged in rows. The heart-wood is of a reddish-brown color, but only 

 seen in the large and very old trees, and the sap-wood, of which the small 

 trees are generally wholly composed, is of a creamy-white color, when 

 freshly cut, but soon assumes a brownish cast, apparently caused by a 

 fermentation of the sap. Specific Gravity, 0.8^53 ; Percentage of Ash, 1. 28; 

 Relative Approximate Fuel Value, 0.8147; Coefficient of Elasticity ', 95276; 

 Modulus of Rupture, 935; Resistance to Longitudinal Pressure, 463; 

 Resistance to Indentation, 235; Weight of a Cubic Foot in Pounds, 51.43. 



USES. Little used except for fuel, for which it is highly prized. 



MEDICINAL PROPERTIES are only those common to other oaks, due to 

 an astringency of the bark. 



138. QUERCUS DENSIFLORA, H. & A. 



TAN-BARK OAK, EVERGREEN CHESTNUT OAK. 



Ger., Eiche mit dichten Blumen ; Fr., Chene afleurs denses; Sp., Rolle 



deflores densas. 



SPECIFIC CHARACTERS. Leaves persistent, oblong, 2-5 in. long, obtuse or acute at 

 apex, rounded, obtuse or sometimes acute at base, with re volute and entire or serrate- 

 dentate margin, often strongly concave below, light glaucous-green above, densely 

 yellowish tomentose beneath, as with the short petioles (-J- in. in length) peduncles, 

 branchlets, etc., with stellate and more or less fugacious hairs. Flowers in dense 

 erect aments (those of all our other oaks being loose and pendent) 3-6 in. long, 

 stamenate above and pistillate below, or some wholly staminate, clustered on the cat- 

 kins in glomerules of three subtended by three bracts; calyx with 5 broad woolly 

 lobes; stamens 10, with long slender much exserted filaments and very small anthers; 



