Quercus john-tuckeri

Nixon & C. H. Muller

Novon 4: 391. 1994.

Common names: Tucker oak desert scrub oak
EndemicIllustrated
Synonyms: Quercus turbinella subsp. californica J. M. Tucker
Treatment appears in FNA Volume 3.

Shrubs, subevergreen or evergreen, 1-3 (-5) m. Bark light gray or brown, scaly. Twigs yellowish or dingy gray, 1-1.5 (-2) mm diam., densely tomentulose. Buds brown, ovoid or globose, 1.5-2 (-3) mm, glabrous except for ciliate margins of scales; proximal scales often yellowish puberulent. Leaves: petiole 1-4 mm. Leaf-blade unicolored, elliptic or obovate, (10-) 15-30 (-40) × (8-) 10-15 (-20) mm, thick and leathery, often brittle, base truncate or rounded-attenuate, rarely subcordate, margins irregularly spinose-toothed, occasionally shallowly lobate, secondary-veins (3-) 4-7, often some veins branching near margin and passing into more than 1 tooth, apex acute or rounded; surfaces abaxially waxy grayish, light green, or yellowish, sparse to moderately dense (8-) 10-12-rayed, (loosely) appressed-stellate hairs, often 0.2-0.5 mm diam., and sparse to crowded, yellowish, glandular-hairs, adaxially dull grayish, with stellate hairs, similar to abaxial surface. Acorns solitary or paired, subsessile; cup cupshaped or obconic to hemispheric, 5-7 mm deep × 10-15 mm wide, thin, scales whitish or yellowish, moderately or scarcely tuberculate, puberulent; nut fusiform, ovoid, or conic, 20-30 mm, apex acute. Cotyledons distinct.


Habitat: Dry slopes, chaparral, pinyon and juniper woodlands, margins of oak woodlands and sagebrush
Elevation: 900-2000 m

Discussion

Dry slopes, chaparral, pinyon and juniper woodlands, margins of oak woodlands and sagebrush; 900-2000 m; Calif.

Endemic to California, Quercus john-tuckeri occurs from Los Angeles County northward in the interior Coast Ranges and Sierra Foothills to the northern edge of Sacramento Valley.

Quercus john-tuckeri bears some resemblance to both Q. turbinella and Q. berberidifolia. Quercus turbinella has pedunculate fruit and cordate leaf bases, however, and Q. berberidifolia has a glabrate adaxial leaf surface, substantially smaller stellate trichomes with fewer rays on the abaxial leaf surface, heavier tuberculate acorn cups, and blunt or rounded (instead of acute) acorns.

Selected References

None.

Lower Taxa

None.
... more about "Quercus john-tuckeri"
paired +  and solitary +
acute +  and rounded +
Kevin C. Nixon +
Nixon & C. H. Muller +
brown;light gray +
subcordate;rounded-attenuate;truncate +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
globose +  and ovoid +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
2-6-lobed +
pistillate +, capitate +  and spicate +
Tucker oak +  and desert scrub oak +
starchy +  and fleshy +
obconic +  and hemispheric +
thin +, ×10-15 +, 5mm +  and 7mm +
multibracteate +, spiny +  and scaly +
900-2000 m +
pistillate +  and staminate +
biennial +, annual +  and maturation +
1-seeded +  and winged +
in groups +  and enclosed +
Dry slopes, chaparral, pinyon and juniper woodlands, margins of oak woodlands and sagebrush +
stellate +  and appressed-stellate +
0.2mm;0.5mm +
pistillate +, spicate +  and staminate +
tomentulose +  and glabrate +
3 cm30 mm <br />0.03 m <br /> (4 cm40 mm <br />0.04 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
obovate +  and elliptic +
thick;10mm;15mm +
arranged +  and alternate +
entire +, dentate +  and serrate +
lobate +  and spinose-toothed +
conic +, ovoid +  and fusiform +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
yellowish +  and whitish +
connate +  and distinct +
few-to-many +
tuberculate +
reduced +
anastomosing +, branching +  and unbranched +
Endemic +  and Illustrated +
inconspicuous +
distinct +
subulate +  and dilated +
enlarged +
yellowish +, light green +, grayish +  and waxy +
sparse;moderately dense +
Quercus turbinella subsp. californica +
Quercus john-tuckeri +
Quercus sect. Quercus +
species +
spheric +  and ovoid terete or angled +
bristle-tipped +
dingy gray +  and yellowish +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
tomentulose +
300 cm3,000 mm <br />3 m <br /> (500 cm5,000 mm <br />5 m <br />) +
evergreen +  and subevergreen +