Oaks of the World

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  Quercus emoryi
Author Torr. 1848 Not. Milit. Reconn. 151
Synonyms balsequillana Trel. 1924 Diagnosis here
duraznillo Diagnosis here, and f. bullata, cochutensis and pinetorum Trel. 1924
hastata Liebm. 1854 Diagnosis here
Local names Emory's oak; black-jack oak ; encino prieto ; bellota ;
Range West Texas to Central Arizona; Mexico (Baja California, Chihuahua, Coahuila, Durango, Nuevo Leon, San Luis Potosi, Sonora, Tamaulipas); 1200-2000 m;
Growth habit 2-5 m high, but may reach sometimes 15 m on favourable soils;
Leaves 2.5-6 x 1-2 cm; subpersistent; thick, stiff; leathery; narrowly oblong, sometimes oboval or oval; apex acute or obtuse, aristate; base subcordate to truncate, less often obtuse, seldom rounded asymmetrical; margin flat, entire or with 1-5 pairs of small aristate teeth; lustrous above, glabrous or with sometimes some sessile fascicled trichomes, essentially at the base of the midrib; less lustrous beneath, hairless or with axil tufts of stipitate fascicled hairs and glandular trichomes somewhat golden; 4-8 vein pairs, not evident; tertiary veins prominent; epidermis slightly bullate and white papillose; petiole pubescent, 3-7 mm long;
Flowers flowers appear in April-May; male catkins 1-3 cm long, with 1-2 flowers 4-staminate; female inflorescence pubescent, very short, with a lonely flower;
Fruits acorn 1.2-1.9 cm, narrow; solitary; cup sessile (or with a very short peduncle to 2 mm), enclosing 1/3 of nut, pubescent inside, with thin, smooth, appressed scales; edible since a little bitter; maturing first year in June - September;

Bark, twigs and

bark dark grey, thick, deeply furrowed; twigs slender, 1-3 mm in diameter, reddish brown, stiff, pubescent when young, with inconspicuous whitish lenticels; bud 2-3 mm, ovoid to elliptical, red brown, pubescent on the scales margin; stipules deciduous, 3-8 mm long;
Hardiness zone, habitat hardy zone 6; all types of soils if dry rocky ones; slow growing;
Miscellaneous -- A. Camus : n° 388;
-- Sub-genus Quercus, section Lobatae, Series Erythromexicanae, Group Vimineae;
-- Discovered by William H. Emory (U.S.A. 1811-1887 )
-- Hybridizes with Q.graciliformis (= Q.x tharpii C.H.Muller), Q. hypoleucoides, and with Q.gravesii (= Q.x robusta);

Subspecies and
-- f. pinetorum Trel. 1924, particularily toothed;