| Quercus x robusta | |
| Author | C.H.Muller 1934 Torreya 34: 119 |
| Synonyms | emoryi x gravesii |
| Local names | Chisos mountains oak |
| Range | Texas (Chisos Mountains, in wet canyons), to 1500 m; |
| Growth habit | reaches 13 m; spreading branches; |
| Leaves | 6-12 cm long, 2-5 cm wide; deciduous; coriaceous, stiff; broadly lanceolate or oval; apex pointed, often long acuminate; base subcordate, or slightly cuneate or truncate, or subcordate; margin unevenly lobed, with 3-5 pairs of aristate teeth, rounded and deep sinuses; both sides glabrous, with persistent hairs above along midrib; beneath frequent axil tufts; 8 vein pairs remotely raised above, prominent beneath; petiole 1-2cm long, pubescent; |
| Flowers | female carkin 5-6 mm or even shorter, bearing1-2 fruits; |
| Fruits | acorn 1.5-2 cm long, oblong, subcylindrical, sometimes elongated, puberulent, with longitudinal stripes; enclosed for 1/4 or 1/3 of length in cup with pointed, tomentose, appressed scales; maturing in 2 years; |
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Bark, twigs and |
bark dark and furrowed, rough; twigs dark brown, 2-3 mm thick, tomentose at first, soon glabrous; numerous small lenticels; bud oblong 3-4 mm; |
| Hardiness zone, habitat | prefers wet places, in mountains; |
| Miscellaneous | -- A.
Camus : tome 3, p. 424, n° 428; -- For C.H. Muller, and for Govaerts & Frodin (1998), it's a true species (fixed hybrid); |
| Subspecies and varieties |
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| Pictures |
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