Oaks of the World

General dataClassificationsList of speciesLocal namesBack to
home page

  Quercus deliquescens
Author C.H.Muller 1979 Phytologia 42: 289
Synonyms
Local names
Range Mexico (Chihuahua, in mountains along the courses of Rio Grande and Rio Conchos); 1700-2100 m; rhizomatous shrub in extensive and dense thickets;
Growth habit 1 m tall; intricate branching;
Leaves 1.2-2.5 (-3) cm long, 1-1.7 (-2) cm broad; evergreen; subcoriaceous or coriaceous; ovate, ovate-elliptical or ovate-lanceolate; apex obtuse sometimes acute, mucronate; base variably cordate; margin undulate slightly revolute, with 2-4 pairs of apiculate teeth, symmetrical and in same number each side; upper surface green or greyish-green, minutely stellate-pubescent with also some simple not glandular trichomes, becoming glabrous; lower surface densely and persistently pale grey-tomentulose, with the same trichomes as on the adaxial side, and also some simple glandular uniseriate ones; 4-6 vein pairs, somewhat impressed above, prominent beneath through the tomentum; epidermis papillose and bullate; petiole 2-4 mm long, pubescent or woolly, as the lower leaf surface;
Flowers staminate catkins 1 cm long, the filiform white-lanate rachis densely flowered, the glabrous anthers barely exerted from the fimbriate calyces; pistillate inflorescences 1- or 2-flowered on a canescent peduncle about 3 mm long;
Fruits acorn 1-1.3 cm, solitary or paired, subsessile or on a persistently pubescent peduncle 2.5-11 mm long; cup hemispheric, 10-15 mm broad, the scales moderately thickened and grey-tomentulose except for the thin, brown, closely appressed, glabrous apices; enclosed 1/3 or less by cup;

Bark, twigs and
buds

bark grey, fissured into irregular, thin plates; twig 1-2 mm thick, densely white or pale grey tomentose, greying and persisting tomentose the second year; buds narrowly ovoid, scarcely 2 mm long, commonly hidden in the pubescence of the crowded petioles; stipules subulate, pubescent, quickly deciduous.
Hardiness zone, habitat limestone slopes and tops of desert mountains in chaparral or thorn-shrub vegetation; hardiness zone 7;
Miscellaneous -- Sub-genus Quercus, Section Quercus, Series Leucomexicanae; 
-- Closely related to Q. intricata Trel., of which it differs in having ovate blades coarsely 2-4 toothed on each side, the margins almost always undulate but never ultimately revolute, the white or light grey tomentum fully covering the midrib and principal veins beneath, veins 4-6 each side (Q. intricata
having blades oblong or elliptic, rarely ovate, usually entire or rarely 1-3 teeth or lobes on each side of a few leaves, margins commonly weakly undulate but always ultimately revolute, the veins beneath glabrous, 8-10 on each side); hybridization between the two species could be easy, but they have not the same range;


Subspecies and
varieties
Pictures