View source for Frangula

{{Treatment/ID
|accepted_name=Frangula
|accepted_authority=Miller
|publications={{Treatment/Publication
|title=Gard. Dict. Abr. ed.
|place=4, vol. 1. 1754
|year=1754
}}
|common_names=Buckthorn
|basionyms=
|synonyms={{Treatment/ID/Synonym
|name=Rhamnus sect. Frangula
|authority=(Miller) de Candolle
|rank=section
}} {{Treatment/ID/Synonym
|name=Rhamnus subg. Frangula
|authority=(Miller) Gray
|rank=subgenus
}}
|hierarchy=Rhamnaceae;Frangula
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Rhamnaceae]]</div><div class="higher-taxon"><small>genus</small>[[Frangula]]</div></div>
|etymology=Probably from Latin frango, to break, and -ula, diminutive, alluding to brittleness of twigs
|volume=Volume 12
|mention_page=page 44
|treatment_page=page 52
}}<!--

--><span class="statement" id="st-undefined" data-properties=""><b>Shrubs </b>or trees, unarmed; bud scales absent, buds hairy. <b>Leaves</b> usually deciduous, sometimes persistent, alternate [rarely opposite], rarely fascicled on short shoots; blade not gland-dotted; pinnately veined, secondary veins nearly straight, parallel. <b>Inflorescences</b> axillary, within foliage, umbels or fascicles, or flowers solitary; peduncles and pedicels not fleshy in fruit. <b>Pedicels</b> present. <b>Flowers</b> bisexual; hypanthium cup-shaped, 1–3 mm wide, usually circumscissile far below sepal bases, rarely not circumscissile; sepals (rarely 4–)5, usually ± erect, sometimes spreading, yellowish to green or white, ovate-triangular, fleshy, keeled adaxially; petals (rarely 4–)5, yellowish, hooded, broadly obovate to obcordate, clawed; nectary thin, lining hypanthium; stamens (rarely 4–)5; ovary superior, (2–)3-locular; style 1. <b>Fruits</b> drupes; stones 2–3(–4), indehiscent but open at base. <b>Seeds</b> obovoid to lenticular, with cartilaginous beak protruding through opening in stone, not furrowed. <b>x</b> = 20–26.</span><!--

-->{{Treatment/Body
|distribution=North America;Mexico;West Indies;Central America;South America;Europe;e Asia;n Africa.
|discussion=<p>Species ca. 50 (7 in the flora).</p><!--
--><p>The difference between <i>Frangula</i> and <i>Rhamnus</i> has long been recognized, but treatments in taxonomic rank have been inconsistent. <i>Frangula</i> was treated within <i>Rhamnus</i> by M. C. Johnston and L. A. Johnston (1978), who noted that <i>Frangula</i> and <i>Rhamnus</i> are more closely related to each other than to other taxa. This observation has been corroborated by molecular studies that show them as sister taxa (J. E. Richardson et al. 2000; K. Bolmgren and B. Oxelman 2004). <i>Frangula</i> was also included within <i>Rhamnus</i> by D. Medan and C. Schirarend (2004) and by Chen Y. L. and C. Schirarend (2007), but various other recent treatments, as here, have maintained them as separate genera, emphasizing the differences outlined above in couplet 13 of the key to genera.</p><!--
--><p>The key to species emphasizes geography as a primary character, reflecting the close similarities among the species and allowing morphological contrasts between sympatric taxa.</p>
|tables=
|references=
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Leaves persistent, semideciduous, or deciduous, blades distinctly coriaceous.
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Leaves persistent; drupes 10–15 mm.
|[[Frangula californica|Frangula californica]]
|-id=key-0-2
|2
|Leaves semideciduous or deciduous; drupes 5–10 mm.
|[[#key-0-3| > 3]]
|-id=key-0-3
|3
|Leaf blades glaucous adaxially when fresh; Plumas County, California.
|[[Frangula purshiana|Frangula purshiana]]
|-id=key-0-3
|3
|Leaf blades not glaucous adaxially; Arizona, Colorado, Nevada, Utah.
|[[Frangula obovata|Frangula obovata]]
|-id=key-0-1
|1
|Leaves deciduous, blades herbaceous to subcoriaceous.
|[[#key-0-4| > 4]]
|-id=key-0-4
|4
|Eastern North America, as far west as Manitoba, Nebraska, and central Texas.
|[[#key-0-5| > 5]]
|-id=key-0-5
|5
|Inflorescences umbels, pedunculate; drupes 8–10 mm; leaf blades oblong to elliptic or obovate-elliptic, margins serrulate to crenulate to nearly entire; drupe stones 3.
|[[Frangula caroliniana|Frangula caroliniana]]
|-id=key-0-5
|5
|Inflorescences fascicles, sessile; drupes 6–8 mm; leaf blades broadly elliptic-obovate to broadly elliptic or broadly oblong, margins entire; drupe stones 2(–3).
|[[Frangula alnus|Frangula alnus]]
|-id=key-0-4
|4
|Western North America, as far east as Colorado, New Mexico, trans-Pecos Texas, and Wyoming.
|[[#key-0-6| > 6]]
|-id=key-0-6
|6
|Inflorescences fascicles, sessile.
|[[Frangula alnus|Frangula alnus]]
|-id=key-0-6
|6
|Inflorescences umbels, pedunculate.
|[[#key-0-7| > 7]]
|-id=key-0-7
|7
|British Columbia, California, Idaho, Montana, w Nevada, Oregon, Washington.
|[[#key-0-8| > 8]]
|-id=key-0-8
|8
|Leaf blades 1.5–8.5 cm; drupe stones 2(–3); inflorescences (2–)4–15-flowered; California, Nevada, Oregon.
|[[Frangula rubra|Frangula rubra]]
|-id=key-0-8
|8
|Leaf blades 6–15 cm; drupes stones 3; inflorescences 10–25-flowered; British Columbia; California, Idaho, Montana, Nevada, Oregon, Washington.
|[[Frangula purshiana|Frangula purshiana]]
|-id=key-0-7
|7
|Arizona, Colorado, s Nevada, New Mexico, Texas, Utah.
|[[#key-0-9| > 9]]
|-id=key-0-9
|9
|Leaf blades elliptic to oblong, elliptic-ovate, or narrowly ovate, 1.6–2.6(–2.9) times longer than wide, ± herbaceous, secondary veins (8–)9–13 pairs; se Arizona, New Mexico, Texas.
|[[Frangula betulifolia|Frangula betulifolia]]
|-id=key-0-9
|9
|Leaf blades obovate to oblong-obovate or oblong, 1.2–1.8(–2.5) times longer than wide, subcoriaceous, secondary veins (5–)6–8(–9) pairs; n Arizona, Colorado, Nevada, Utah.
|[[Frangula obovata|Frangula obovata]]
|}
</div></div><!--

-->{{#Taxon:
name=Frangula
|author=John O. Sawyer†;Guy L. Nesom
|authority=Miller
|rank=genus
|parent rank=family
|synonyms=Rhamnus sect. Frangula;Rhamnus subg. Frangula
|basionyms=
|family=Rhamnaceae
|distribution=North America;Mexico;West Indies;Central America;South America;Europe;e Asia;n Africa.
|reference=None
|publication title=Gard. Dict. Abr. ed.
|publication year=1754
|special status=
|source xml=https://bitbucket.org/aafc-mbb/fna-data-curation/src/2e0870ddd59836b60bcf96646a41e87ea5a5943a/coarse_grained_fna_xml/V12/V12_897.xml
|genus=Frangula
}}<!--

-->[[Category:Treatment]][[Category:Rhamnaceae]]