View source for Quercus havardii

{{Treatment/ID
|accepted_name=Quercus havardii
|accepted_authority=Rydberg
|publications={{Treatment/Publication
|title=Bull. New York Bot. Gard.
|place=2: 213. 1901
|year=1901
}}
|common_names=Havard oak
|special_status={{Treatment/ID/Special_status
|code=E
|label=Endemic
}}{{Treatment/ID/Special_status
|code=F
|label=Illustrated
}}{{Treatment/ID/Special_status
|code=W
|label=Weedy
}}
|basionyms=
|synonyms=
|hierarchy=Fagaceae;Quercus;Quercus sect. Quercus;Quercus havardii
|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 havardii]]</div></div>
|volume=Volume 3
|mention_page=
|treatment_page=
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Shrubs,</b> deciduous, low, forming clones 0.3-1.5 × 10 m, rhizomatous. <b>Bark</b> light gray, scaly-papery. <b>Twigs</b> brown or grayish, 1-2.5 mm diam., glabrous or densely short grayish or yellowish tomentulose, glabrate in age. <b>Buds</b> dark red-brown, subglobose, ca. 2 mm, sparsely pubescent. <b>Leaves</b>: petiole to 7 mm. <b>Leaf</b> blade green, often turning brownish with age, polymorphic, oblong or elliptic or sometimes lanceolate to oblanceolate or ovate to obovate, (30-)50-100 × (10-)20-50 mm, rather thick and hard, base rounded to cuneate, margins flat to revolute, at least some undulate, 2-3 rounded teeth on each side, secondary veins 5-8 on each side, much branched, apex broadly rounded, rarely acute; surfaces abaxially densely grayish or yellowish tomentulose or stellate-pubescent, sometimes only sparsely pubescent, secondary veins quite prominent, adaxially lustrous, very sparsely stellate-pubescent or glabrate, secondary veins very slightly if at all raised. <b>Acorns</b> solitary or paired, subsessile or on peduncle to 10(-18) mm; cup from deeply cup-shaped to goblet-shaped, 10-12 mm deep × 15-25 mm wide, enclosing 1/3-1/2 nut, base rounded or slightly constricted, margin very thin and smooth, scales reddish brown, triangular-ovate to long-acute, proximally moderately to markedly tuberculate, pubescent, often canescent, tips loosely appressed; nut brown, ovoid, 12-25 × 14-18 mm. <b>Cotyledons</b> distinct.</span><!--

-->{{Treatment/Body
|phenology=Flowering spring.
|habitat=Deep, shifting or stabilized sand dunes, off deep sands in putative hybrid populations
|elevation=500-1500 m
|distribution=N.Mex.;Okla.;Tex.
|discussion=<p>Individual clones emerging to heights of 2-3 m from thickets occur sporadically across the Texas range of <i>Quercus havardii</i> and express some characteristics of <i>Q. stellata</i>, such as more deeply lobed leaves and smaller acorns. Such putative hybrids increase in frequency in the eastern part of the range of the species.</p><!--
--><p>Material of <i>Quercus havardii</i> from the Navajo Basin of Utah and adjacent Arizona has been treated as <i>Q. havardii</i> var. tuckeri Welsh. Welsh followed J. M. Tucker (1970) and interpreted these intermediate populations as putative hybrids between <i>Q. havardii</i> and both <i>Q. turbinella</i> and <i>Q. gambelii</i>. Giving varietal rank, instead of nothospecies status, to such populations seems arbitrary, and it certainly is inconsistent with their putative hybrid origins.</p>
|tables=
|references={{Treatment/Reference
|id=tucker1970a
|text=Tucker, J. M. 1970. Studies in the Quercus undulata complex. IV. The contribution of Q. havardii. Amer. J. Bot. 57: 71-84.
}}
}}<!--

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-->{{#Taxon:
name=Quercus havardii
|authority=Rydberg
|rank=species
|parent rank=section
|synonyms=
|basionyms=
|family=Fagaceae
|phenology=Flowering spring.
|habitat=Deep, shifting or stabilized sand dunes, off deep sands in putative hybrid populations
|elevation=500-1500 m
|distribution=N.Mex.;Okla.;Tex.
|reference=tucker1970a
|publication title=Bull. New York Bot. Gard.
|publication year=1901
|special status=Endemic;Illustrated;Weedy
|source xml=https://jpend@bitbucket.org/aafc-mbb/fna-data-curation.git/src/f50eec43f223ca0e34566be0b046453a0960e173/coarse_grained_fna_xml/V3/V3_581.xml
|genus=Quercus
|section=Quercus sect. Quercus
|species=Quercus havardii
}}<!--

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