View source for Quercus engelmannii

{{Treatment/ID
|accepted_name=Quercus engelmannii
|accepted_authority=Greene
|publications={{Treatment/Publication
|title=Ill. W. Amer. Oaks
|place=1: 33, plate 17. 1889
|year=1889
}}
|common_names=Engelmann oak
|special_status={{Treatment/ID/Special_status
|code=F
|label=Selected by author to be illustrated
}}
|basionyms=
|synonyms=
|hierarchy=Fagaceae;Quercus;Quercus sect. Quercus;Quercus engelmannii
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Fagaceae]]</div><div class="higher-taxon"><small>genus</small>[[Quercus]]</div><div class="higher-taxon"><small>section</small>[[Quercus sect. Quercus]]</div><div class="higher-taxon"><small>species</small>[[Quercus engelmannii]]</div></div>
|volume=Volume 3
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Trees,</b> subevergreen, to 10 m. <b>Bark</b> gray or whitish, closely furrowed. <b>Twigs</b> light brown, 1-1.5 mm diam., densely or sparsely stellate-tomentose, soon glabrate. <b>Buds</b> reddish brown, subspheric to broadly ovoid, 1-2 mm, glabrous or basal scales pubescent; stipules persistent about terminal buds. <b>Leaves</b>: petiole (2-)3-4(-6) mm. <b>Leaf</b> blade oblong to elliptic, occasionally lanceolate or ovate, (20-)30-60(-80) × (5-)10-20(-25) mm, base cuneate to cordate, margins entire, undulate, sometimes irregularly toothed, especially toward apex, secondary veins 7-8(-10) on each side, branched, apex acute or broadly rounded; surfaces abaxially blue-green or pale green, densely and loosely glandular-tomentose, quickly glabrate or persistently floccose, especially about base of midrib, at maturity strongly glaucous, adaxially gray-green or pale green, bluish green or glaucous. <b>Acorns</b> solitary or paired, subsessile or on peduncle to 5-6 mm; cup cup-shaped or shallowly cup-shaped, 8-10 mm deep × 10-15 mm wide, enclosing 1/3 nut, scales 1.5-3 mm wide, strongly and regularly tuberculate near base of cup, gray-pubescent; nut light brown, ovoid or oblong, 15-25 × 12-14 mm, glabrate or puberulent about apex. <b>Cotyledons</b> connate. <b>2n</b> = 24.</span><!--

-->{{Treatment/Body
|phenology=Flowering in spring.
|habitat=Oak woodlands, margins of chaparral, arroyos, slopes and bajadas
|elevation=50-1200 m
|distribution=Calif.;Mexico (Baja California).
|discussion=<p><i>Quercus engelmannii</i> is closely related to and possibly conspecific with <i>Q. oblongifolia</i>. The cups of <i>Q. engelmannii</i> are larger, deeper, and generally more tuberculate than those of <i>Q. oblongifolia</i>, and the scales are usually larger. Based on available samples, the nuts of <i>Q. engelmannii</i> are consistently larger than those of <i>Q. oblongifolia</i>, apparently with little, if any, overlap in diameter. Considerably more variation occurs within <i>Q. engelmannii</i> in leaf form, possibly reflecting introgression from other white oak species such as <i>Q. cornelius-mulleri</i>, <i>Q. dumosa</i>, and <i>Q. durata</i> (see treatment).</p><!--
--><p>On Catalina Island, <i>Quercus engelmannii</i> is known only from a small grove of trees. Putative hybrids between <i>Q. engelmannii</i> and <i>Q. cornelius-mulleri</i> are common in areas of contact between the two species in Riverside and San Diego counties in southern California. Such a population was the basis for Q. acutidens Torrey [<i>Q. dumosa</i> var. acutidens (Torrey) Wenzig]. Other names applied to those populations are Q. macdonaldii var. elegantula Greene and <i>Q. dumosa</i> var. elegantula (Greene) Jepson. Variable in leaf form and stature, those intermediates form extensive populations and are probably best disposed of under the name Q. ×acutidens.</p>
|tables=
|references=
}}<!--

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-->{{#Taxon:
name=Quercus engelmannii
|author=
|authority=Greene
|rank=species
|parent rank=section
|synonyms=
|basionyms=
|family=Fagaceae
|phenology=Flowering in spring.
|habitat=Oak woodlands, margins of chaparral, arroyos, slopes and bajadas
|elevation=50-1200 m
|distribution=Calif.;Mexico (Baja California).
|reference=None
|publication title=Ill. W. Amer. Oaks
|publication year=1889
|special status=Selected by author to be illustrated
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse_grained_fna_xml/V3/V3_542.xml
|genus=Quercus
|section=Quercus sect. Quercus
|species=Quercus engelmannii
}}<!--

-->[[Category:Treatment]][[Category:Quercus sect. Quercus]]