View source for Silphium

{{Treatment/ID
|accepted_name=Silphium
|accepted_authority=Linnaeus
|publications={{Treatment/Publication
|title=Sp. Pl.
|place=2: 919. 1753
|year=1753
}}, {{Treatment/Publication
|title=Gen. Pl. ed.
|place=5, 391. 1754
|year=1754
}}
|basionyms=
|synonyms=
|hierarchy=Asteraceae;Asteraceae tribe Heliantheae;Asteraceae (tribe Heliantheae) subtribe Ecliptinae;Silphium
|hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Heliantheae]]</div><div class="higher-taxon"><small>subtribe</small>[[Asteraceae (tribe Heliantheae) subtribe Ecliptinae]]</div><div class="higher-taxon"><small>genus</small>[[Silphium]]</div></div>
|etymology=Greek silphion, an unknown plant appearing on ancient coins of the city of Cyrene
|volume=Volume 21
|mention_page=page 65, 157
|treatment_page=page 77
}}<!--

--><span class="statement" id="st-d0_s0" data-properties="whole-organism some measurement;whole-organism duration"><b>Perennials,</b> 20–250+ cm (fibrous-rooted, rhizomatous, or taprooted).</span> <span class="statement" id="st-d0_s1" data-properties="stem orientation;stem architecture"><b>Stems </b>usually erect, usually branched (terete or square, often vernicose with resinous exudates).</span> <span class="statement" id="st-d0_s2" data-properties=""><b>Leaves </b>basal and cauline (basal persistent or withering before flowering);</span> <span class="statement" id="st-d0_s3" data-properties="">whorled, opposite, subopposite, or alternate (sometimes all conditions on one plant);</span> <span class="statement" id="st-d0_s4" data-properties="leaf position;leaf position;leaf arrangement;leaf arrangement;leaf arrangement;leaf arrangement;leaf arrangement;leaf arrangement;leaf architecture;leaf architecture">petiolate or sessile;</span> <span class="statement" id="st-d0_s5" data-properties="blade shape;blade arrangement or shape;blade shape;blade shape;blade shape;blade shape;blade shape;blade shape;blade shape;base shape;margin shape;margin shape;face pubescence;face pubescence">blades (1-nerved or 3-nerved) deltate, elliptic, linear, ovate, or rhombic, sometimes 1–2-pinnately lobed or pinnatifid, bases cordate or truncate to cuneate, margins entire or toothed, faces glabrous or hairy (sometimes stipitate-glandular).</span> <span class="statement" id="st-d0_s6" data-properties="head architecture or arrangement;array architecture;array architecture"><b>Heads </b>radiate, in paniculiform or racemiform arrays.</span> <span class="statement" id="st-d0_s7" data-properties="involucre shape;involucre diameter"><b>Involucres </b>campanulate to hemispheric, 10–30 mm diam.</span> <span class="statement" id="st-d0_s8" data-properties="phyllary duration;phyllary quantity;series quantity"><b>Phyllaries </b>persistent, 11–45 in 2–4 series (outer broader, foliaceous, inner smaller, thinner, each subtending a ray-floret).</span> <span class="statement" id="st-d0_s9" data-properties="receptacle shape;receptacle architecture"><b>Receptacles </b>flat to slightly convex, paleate (paleae oblong, lanceolate, or linear).</span> <span class="statement" id="st-d0_s10" data-properties="ray-floret quantity;ray-floret architecture;ray-floret reproduction;series quantity"><b>Ray-</b>florets 8–35+ in 1–4 series, pistillate, fertile;</span> <span class="statement" id="st-d0_s11" data-properties="corolla coloration;corolla coloration">corollas yellow or white.</span> <span class="statement" id="st-d0_s12" data-properties="disc-floret quantity;disc-floret architecture"><b>Disc-</b>florets 20–200+, functionally staminate;</span> <span class="statement" id="st-d0_s13" data-properties="corolla coloration;corolla coloration;tube height or length or size;throat size or width;throat shape;lobe quantity;lobe shape">corollas yellow or white, tubes much shorter than narrow, cylindric throats, lobes 5, deltate.</span> <span class="statement" id="st-d0_s14" data-properties=""><b>Cypselae </b>(black to brown) obflattened (± winged, shed alone without accessory structures);</span> <span class="statement" id="st-d0_s15" data-properties="awn quantity">pappi 0, or persistent, of 2 awns (± confluent with cypsela shoulders and wings).</span> <span class="statement" id="st-d0_s16" data-properties="pappus presence;pappus duration;x chromosome quantity">x = 7.</span><!--

-->{{Treatment/Body
|distribution=North America
|discussion=<p>Species 12 (12 in the flora).</p><!--
--><p>In keys and descriptions here, “plants scapiform” indicates plants with distal cauline leaves notably smaller than basal and proximal cauline leaves, and “plants caulescent” indicates plants with leaves ± uniform in size throughout; “leaves persistent” indicates leaves persisting to flowering time, and “leaves caducous” indicates leaves withering before flowering time.</p>
|tables=
|references={{Treatment/Reference
|id=perry1937a
|text=Perry, L. M. 1937. Notes on Silphium. Rhodora 39: 281–297.
}}
}}<!--

--><div class="treatment-key">
==Key==
<div class="treatment-key-group">
  
{| class="wikitable fna-keytable"
|-id=key-0-1
|1
|Stems square (distal leaf or petiole bases connate-perfoliate)
|[[Silphium perfoliatum|Silphium perfoliatum]]
|-id=key-0-1
|1
|Stems terete or slightly 4-angled (distal leaves not perfoliate)
|[[#key-0-2| > 2]]
|-id=key-0-2
|2
|Leaves (at least proximal) usually laciniate, pinnatifid, or 1–2-pinnately lobed (lobes 3–15)
|[[#key-0-3| > 3]]
|-id=key-0-2
|2
|Leaves (proximal and distal) seldom lobed (sometimes with 2 basal lobes, then hastate, sagittate, or auriculate)
|[[#key-0-6| > 6]]
|-id=key-0-3
|3
|Ray florets 6–12
|[[Silphium compositum|Silphium compositum]]
|-id=key-0-3
|3
|Ray florets 14–40
|[[#key-0-4| > 4]]
|-id=key-0-4
|4
|Corollas white
|[[Silphium albiflorum|Silphium albiflorum]]
|-id=key-0-4
|4
|Corollas yellow
|[[#key-0-5| > 5]]
|-id=key-0-5
|5
|Phyllaries appressed, apices acute to obtuse
|[[Silphium terebinthinaceum|Silphium terebinthinaceum]]
|-id=key-0-5
|5
|Phyllaries reflexed or appressed, apices acuminate to caudate
|[[Silphium laciniatum|Silphium laciniatum]]
|-id=key-0-6
|6
|Plants taprooted (scapiform; cauline leaves notably smaller distally)
|[[#key-0-7| > 7]]
|-id=key-0-6
|6
|Plants fibrous rooted (caulescent; cauline leaves not notably smaller distally)
|[[#key-0-8| > 8]]
|-id=key-0-7
|7
|Ray flowers 6–12
|[[Silphium compositum|Silphium compositum]]
|-id=key-0-7
|7
|Ray flowers 17–29
|[[Silphium terebinthinaceum|Silphium terebinthinaceum]]
|-id=key-0-8
|8
|Leaves (at least proximal leaves) petiolate (never sessile), bases truncate, cordate, auriculate, hastate, or sagittate
|[[#key-0-9| > 9]]
|-id=key-0-8
|8
|Leaves (proximal and distal) petiolate (blade bases round to tapered) or sessile (blade bases round to cordate)
|[[#key-0-10| > 10]]
|-id=key-0-9
|9
|Stems glabrous; basal leaves caducous
|[[Silphium brachiatum|Silphium brachiatum]]
|-id=key-0-9
|9
|Stems hispid; basal leaves persistent
|[[Silphium wasiotense|Silphium wasiotense]]
|-id=key-0-10
|10
|Phyllaries: abaxial faces usually glabrous (rarely scabrous in outer series)
|[[#key-0-11| > 11]]
|-id=key-0-10
|10
|Phyllaries: abaxial faces glandular, hirsute, hispid, or scabrous
|[[#key-0-12| > 12]]
|-id=key-0-11
|11
|Ray florets 20–36+
|[[Silphium integrifolium|Silphium integrifolium]]
|-id=key-0-11
|11
|Ray florets 8–17
|[[Silphium asteriscus|Silphium asteriscus]]
|-id=key-0-12
|12
|Leaf faces stipitate-glandular
|[[Silphium glutinosum|Silphium glutinosum]]
|-id=key-0-12
|12
|Leaf faces eglandular
|[[#key-0-13| > 13]]
|-id=key-0-13
|13
|Basal leaves persistent
|[[#key-0-14| > 14]]
|-id=key-0-13
|13
|Basal leaves caducous
|[[#key-0-15| > 15]]
|-id=key-0-14
|14
|Leaf faces shaggy-hispid; phyllaries hispid; corollas pale yellow; cypselae 6–10mm; Alabama, Georgia, Tennessee
|[[Silphium mohrii|Silphium mohrii]]
|-id=key-0-14
|14
|Leaf faces hirsute, hispid, or scabrous; phyllaries scabrous; corollas bright yellow; cypselae 10–17 mm; Louisiana, Texas
|[[Silphium radula|Silphium radula]]
|-id=key-0-15
|15
|Cauline leaves opposite (clasping stems)
|[[Silphium integrifolium|Silphium integrifolium]]
|-id=key-0-15
|15
|Cauline leaves opposite or alternate (not clasping stems)
|[[#key-0-16| > 16]]
|-id=key-0-16
|16
|Ray florets 20–30+
|[[Silphium radula|Silphium radula]]
|-id=key-0-16
|16
|Ray florets 12–20
|[[Silphium asteriscus|Silphium asteriscus]]
|}
</div></div><!--

-->{{#Taxon:
name=Silphium
|author=Jennifer A. Clevinger
|authority=Linnaeus
|rank=genus
|parent rank=subtribe
|synonyms=
|basionyms=
|family=Asteraceae
|distribution=North America
|reference=perry1937a
|publication title=Sp. Pl.;Gen. Pl. ed.
|publication year=1753;1754
|special status=
|source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V19-20-21/V21_168.xml
|tribe=Asteraceae tribe Heliantheae
|subtribe=Asteraceae (tribe Heliantheae) subtribe Ecliptinae
|genus=Silphium
|array architecture=racemiform;paniculiform
|awn quantity=2
|base shape=truncate;cuneate
|blade arrangement or shape=elliptic
|blade shape=pinnatifid;lobed;rhombic;ovate;rhombic;ovate;linear;deltate
|corolla coloration=white;yellow;white;yellow
|disc-floret architecture=staminate
|disc-floret quantity=20;200
|face pubescence=hairy;glabrous
|head architecture or arrangement=radiate
|involucre diameter=10mm;30mm
|involucre shape=campanulate;hemispheric
|leaf architecture=sessile;petiolate
|leaf arrangement=alternate;subopposite;alternate;subopposite;opposite;whorled
|leaf position=cauline;basal
|lobe quantity=5
|lobe shape=deltate
|margin shape=toothed;entire
|pappus duration=persistent
|pappus presence=absent
|phyllary duration=persistent
|phyllary quantity=11;45
|ray-floret architecture=pistillate
|ray-floret quantity=8;35
|ray-floret reproduction=fertile
|receptacle architecture=paleate
|receptacle shape=flat;slightly convex
|series quantity=1;4
|stem architecture=branched
|stem orientation=erect
|throat shape=cylindric
|throat size or width=narrow
|tube height or length or size=much shorter
|whole-organism duration=perennial
|whole-organism some measurement=20cm;250cm
|x chromosome quantity=7
}}<!--

-->[[Category:Treatment]][[Category:Asteraceae (tribe Heliantheae) subtribe Ecliptinae]]