iisisting < 



QUERCUS 



erect catkins with 4-7-parted calyx ami 4-12, usually 6, 

 stamens; pistillate in 1-many-fld. spikes in the axils o£ 

 the young Ivs., rarely at the base of the axillary stami- 

 nate catkins, each flower consisting of an incompletely 

 3-celled ovary, surrounded by imbricate 

 bracts: fr. a 1 -seeded subglobose to oblong 

 nut, surrounded at the base or sometimes al- 

 most inclosed by a cup-like involucre. 



The numerous species have been divided 

 into different sub^'iii'-rii \!l 

 cles, except Q. <!■ •< i i 



genus Lepidobiilan . 

 "acorn"), which i- . ;: ; , 

 pendulous, staniiiKiii; < ari.iu-. 

 lary pistillate spikes ;ind a cup 

 bracts of various shape but not 

 zones. Q. densiflora belongs to Pasania, 

 which has erect staminate catkins, some bear- 

 ing pistillate fls. at their base, like the catkins 

 of Castanea. Cyclobalanus and Cyclobala- 

 nopsis have the scales of the cup connate into 

 concentric rings; the inflorescence of the flrst 

 being similar to that of Pasania, of the second 

 to Lepidobalanus. Chlamydobalanus is much 

 like Cyclobalanus, but the nut is wholly in- 

 cluded by the ovate cup. Of Lithocarpus. 

 with the nut partly connate with the cup, but 

 otherwise like the last-named subgenus, no 

 species is in cultivation. The oaks of the 

 subgenus Lepidobalanus are divided into 

 two sections, — Leucobalanus and Melanoba- 

 lanus. In the former, comprising the White 

 Oak tribe, the acorns mature the first year 

 (Fig. 2039). In the latter, comprising the 

 Black Oaks, the acorns mature the second 

 year (Fig. 2040). Besides the 300 species, 

 about 40 hybrids have been recorded. The 

 latest monograph of the whole genus is by 

 A. DeCandolle in Prodromus, vol. 16, 2, pp. 

 1-108(18(54-1868). Important illustrated works 

 ican Oaks are A. Michaux. "Histoire des Chenes de 

 I'Amerique" (1801), with 36 plates; Kellogg and Greene. 

 "Illustrations of West American Oaks" (1889), with 37 

 plates; Sargent," Silva of North America," vol. 8 (1895), 

 with 82 plates, and Liebmann. "Chenes de TAmerique 

 tropicale" (1869), witli IT I'hitev. Most of the European 

 and west Asian Oaks me Hi.'iire.l in Kotschy, Eichen 

 Europas und des Orients ( l.siL'i. with 40 colored plates. 



wagons, tools and many other articles. The bark of 

 some species, in America that of Q. vrlutimi, Prinua 

 and densiflora, is used for tanning leather. Cork is 

 obtained from the bark of Q. Siiber and ocridentalis in 



1 Amer- 



southern Europe. The bark of a few species has also 

 been employed in medicine. The acorns of several spe- 

 cies are edible, in America especially those of Q. 

 Michauxi, Emory i and lobata; in Europe those of Q. 

 Ilex, var. Ballota and ^gilops; in Japan those of 

 Q. glauca; in many European countries the acorns of 

 all species are an important food for hogs. In eastern 

 Asia a silkworm feeds on the leaves of different species. 

 A parasitic insect living on Q. coceifera in southern 

 Europe and N. Africa yields a scarlet dye. (Sails caused 

 by the puncture of certain insects are used for tanning 

 and dyeing and are now chiefly obtained from Q. Ilex, 

 var. infectoria in western Asia. Some of the above men- 

 tioned species are described only in the supplementary 

 list, p. 1483. See On!;. 



The Oaks comprise some of the most important forest 

 trees of the northern hemisphere. The wood of most 

 species is strong, tough, hard and durable, and highly 

 valued for many purposes, especially ship-building, 

 eonstruction, for furniture, and in the manufacture of 



