Oaks of the World

General dataClassificationsList of speciesLocal namesBack to
home page

 Quercus canbyi
AuthorTrel. 1924
Synonymsalamarensis C.H.Mull. 1942
graciliformis C.H.Mull 1934
graciliformis f. parvilobata (C.H.Mull.) C.H.Mull. 1940
graciliformis var. parvilobata C.H.Mull. 1934
graciliramis C.H.Mull. 1936 (A.Camus n° 393)
karwinskii Trel. 1924
Local nameschisos oak; slender oak; canby oak; graceful oak;
Range Mexico (Coahuila, Nuevo Leon, Tamaulipas); Texas (Chisos Mountains ) ; from 0 to 2100 m in rocky canyons ; restricted area;
Growth habit4-15 m tall, with trunk 20-50 cm in diameter; long flexible branches somewhat drooping;
Leaves 6-10 x 2-4 cm; semi-evergreen or lately deciduous; thick, leathery; lanceolate to narrowly ovate; apex pointed, attenuate, bristle-tipped; base acute, attenuate or cuneate; margin thick, flat or slightly revolute, with 3-5 pairs of bristle-tipped, short teeth (from base to apex, or only on the apical 2/3) withe shallow sinuses, or sometimes entire; dark shiny green above, hairless or with shorts stellate hairs, and glandular hairs mostly along veins; dull, yellowish-green beneath, glabrous or with sometimes axil tufts; 6-10 vein pairs, mostly straight; petiole hairless, slender, flexible, 1-2 cm long;
Flowers April-May; male catkins pubescent, 3-5 cm long, with 20-30 flowers; pistillate ones 0.5-1 cm long, 1 or 2-flowered;
Fruits acorn 1-1.5 cm, ovoid; stalkless or nearly so; singly or to 3 together; cup very shallow covering 1/2 or 1/3 of nut, with nearly flat scales; maturing in 1 or 2 years;

Bark, twigs and
buds

bark brown green, smooth, becoming dark grey, warty, sulcate; twig red brown, shiny, thin (1-2 mm in diameter), soon glabrous, with rare, light lenticels; terminal bud red brown, ovoid, 1.5-3 mm, shortly ciliate;
Hardiness zone, habitat hardy zone 7; prefers dry, rocky soils;
Miscellaneous -- A. Camus : n° 384;
-- section Lobatae, sub-section Acutifoliae;
-- confusion is possible with Q. albocincta, which has ovate or elliptic leaves, more veins pairs, longer teeth, longer bristle-tips and longer petioles.
Subspecies and
varieties
--- Q.canbyi has been described as a variety of Q.graciliformis in the south of its range (North Mexico), and differs from the type in having acorns maturing in 1 year, less lobes (4 pairs instead of 5...), and a shallower cup. In fact, it seems that it is nothing but a geographical form...For today's Mexican Authors (Silvia Romero Rangel, 2006), the accepted name is Q.canbyi, and Q.graciliformis is the synonym...
--- Q.alamarensis : for today's Mexican Authors (Susana Valencia-Avalos, 2004), this taxon described by Muller is doubfull, maybe a hybrid or a morphological, isolated variation...
--- Q.langtry (Langtry Oak) ; first considered as synonymous for Q.gravesii in 1850, is currently defined as a member of the graciliformis-canbyi group; discovered near Langtry (Texas), it bears 2 years maturing acorns and a greater number of lobes (5-7 instead of 2-5); but more studies are necessary to precise the taxonomical place of this species; hardiness zone : 7;
Pictures