| Quercus engelmannii | |
| Author | Greene 1889 Ill. W. Amer. Oaks 1: 32 |
| Synonyms | |
| Local names | Engelmann's
oak; mesa oak ; evergreeen white oak ; |
| Range | Northeast
California, Santa Catalina Island; Mexico; to 1200 m; restricted area;
|
| Growth habit | reaches 15 m high, with trunk to 70 cm in diameter; branches low on the trunk; crown open, spreading; |
| Leaves | 2.5-7
x 1.2-2.5 cm; evergreen or nearly so (leaves may fall during drought summers);
oblong or elliptic; thick, leathery; apex rounded; base variable; margin
entire or minutely dentate near apex; blue green, glabrous, smooth, not
rough above; yellow green beneath with stellate trichomes with long rays,
persisting at least on the base of midrib; 7-8 vein pairs, inconspicuous;
petiole 3-7 mm; |
| Flowers | male
flowers in April-May on 3-4 cm catkins; |
| Fruits | acorn
1.5-2.5 cm long, pale grey, elliptic, subsessile, striate near apex; single
or paired, on a very short rachis; cup enclosing 1/3 to 1/2 of nut, strongly
warty near the base; maturing in 1 year; |
|
Bark, twigs and |
bark
light grey, finely striate; twigs stiff, brown, hairy; bud red brown,
globose, glabrous, 1-2 mm; |
| Hardiness zone, habitat | almost
hardy (zone 8 but withstands -14°C); all types of dry and hot soils,
but thrives better in moist ones; |
| Miscellaneous | --
Sub-genus Quercus, Section Quercus, Series Leucomexicanae, Group Glaucoideae; -- A. Camus : n° 181 ; -- Threatened (IUCN Red List Category : EN). -- Closely related to Q.oblongifolia Torr., and maybe conspecific, with cup scales deeper, larger and more warty; -- George Engelmann (1809-1884) was botanist at Saint-Louis, of German origin; -- Hybridizes with Q.dumosa and Q.lobata. |
| Subspecies and varieties |
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| Pictures |
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