View source for Petasites ← Petasites You do not have permission to edit this page, for the following reason: The action you have requested is limited to users in the group: Users. You can view and copy the source of this page. {{Treatment/ID |accepted_name=Petasites |accepted_authority=Miller |publications={{Treatment/Publication |title=Gard. Dict. Abr. ed. |place=4, vol. 3. 1754 |year=1754 }} |common_names=Butterbur;coltsfoot;pétasite |basionyms= |synonyms= |hierarchy=Asteraceae;Asteraceae tribe Senecioneae;Petasites |hierarchy_nav=<div class="higher-taxa"><div class="higher-taxon"><small>family</small>[[Asteraceae]]</div><div class="higher-taxon"><small>tribe</small>[[Asteraceae tribe Senecioneae]]</div><div class="higher-taxon"><small>genus</small>[[Petasites]]</div></div> |etymology=Attributed to Dioscorides, Greek petasos, broad-brimmed hat, alluding to large basal leaves |volume=Volume 20 |mention_page=page 541, 542, 543, 636, 637 |treatment_page=page 635 }}<!-- --><span class="statement" id="st-d0_s0" data-properties="whole-organism atypical some measurement;whole-organism some measurement;whole-organism duration"><b>Perennials,</b> 10–25 (–120) cm (plants rhizomatous, polygamodioecious).</span> <span class="statement" id="st-d0_s1" data-properties="stem orientation;stem architecture"><b>Stems </b>erect, not branched (± scapiform; stems of “staminate” plants wither soon after flowering, stems of “pistillate” plants elongate after flowering).</span> <span class="statement" id="st-d0_s2" data-properties=""><b>Leaves </b>basal and cauline;</span> <span class="statement" id="st-d0_s3" data-properties="">alternate;</span> <span class="statement" id="st-d0_s4" data-properties="leaf position;leaf position;leaf arrangement;leaf architecture;leaf architecture">petiolate or sessile;</span> <span class="statement" id="st-d0_s5" data-properties="basal leaf architecture;basal leaf shape;margin shape;margin shape;margin shape;abaxial face pubescence;adaxial leaf pubescence;adaxial leaf pubescence;adaxial leaf pubescence">basal (usually appearing after heads) palmately or palmati-pinnately nerved, mostly deltate to ovate or orbiculate, margins entire, denticulate, or toothed to lobed, abaxial faces ± tomentose, adaxial tomentulose and glabrescent or glabrous;</span> <span class="statement" id="st-d0_s6" data-properties="cauline leaf shape">cauline (sessile) bractlike (essentially expanded petioles, proximal sometimes bearing blades).</span> <span class="statement" id="st-d0_s7" data-properties="head architecture or arrangement;head architecture or shape;head architecture or shape;head arrangement;array architecture;array architecture;array architecture"><b>Heads </b>radiate, discoid, or disciform, usually in corymbiform, paniculiform, or racemiform arrays, rarely borne singly {“staminate” heads usually radiate, peripheral 1–20 (–70) florets styliferous and sterile or neuter, inner 11–78 florets usually functionally staminate, rarely bisexual and fertile; “pistillate” heads usually radiate, peripheral (1–) 30–130+ florets pistillate and fertile, inner 1–12 florets functionally staminate}.</span> <span class="statement" id="st-d0_s8" data-properties="calyculus presence;calyculus quantity;bractlet quantity"><b>Calyculi </b>0 or of 1–5+ bractlets.</span> <span class="statement" id="st-d0_s9" data-properties=""><b>Involucres </b>obconic to turbinate, 6–15+ mm diam.</span> <span class="statement" id="st-d0_s10" data-properties="involucre shape;involucre diameter">(expanding in fruit).</span> <span class="statement" id="st-d0_s11" data-properties="phyllarie duration;phyllarie quantity;phyllarie orientation;phyllarie fusion;phyllarie fusion;phyllarie shape;phyllarie size;series atypical quantity;series quantity;margin texture"><b>Phyllaries </b>persistent, mostly 12–15 in (1–) 2 series (often purplish-tinged), erect, distinct or connate, narrowly oblong to linear (1–5-nerved), subequal, margins ± scarious (apices not black).</span> <span class="statement" id="st-d0_s12" data-properties="receptacle shape;receptacle relief;receptacle architecture"><b>Receptacles </b>flat to convex, foveolate, epaleate.</span> <span class="statement" id="st-d0_s13" data-properties="ray-floret presence;ray-floret atypical quantity;ray-floret quantity;ray-floret reproduction;ray-floret architecture;ray-floret reproduction;ray-floret architecture"><b>Ray-</b>florets 0 or (1–) 30–130+, usually fertile (in pistillate heads), sometimes styliferous and sterile or neuter (in staminate heads);</span> <span class="statement" id="st-d0_s14" data-properties="corolla coloration">corollas whitish or pinkish to purplish [yellow] (tubes filiform, laminae linear to oblong; styles filiform to clavate, entire or shallowly 2-cleft, papillate).</span> <span class="statement" id="st-d0_s15" data-properties="peripheral floret quantity;peripheral floret reproduction;peripheral floret presence"><b>Peripheral </b>(pistillate) florets usually 30–125 and fertile, sometimes 0;</span> <span class="statement" id="st-d0_s16" data-properties="corolla coloration">corollas whitish or pinkish to purplish [yellow] (filiform, usually 5-lobed, sometimes minutely bilabiate; styles filiform to clavate, entire or shallowly 2-cleft, papillate).</span> <span class="statement" id="st-d0_s17" data-properties="inner floret quantity;inner floret architecture;inner floret reproduction;inner floret reproduction"><b>Inner </b>(functionally staminate or bisexual) florets 1–78, usually functionally staminate, rarely bisexual and fertile;</span> <span class="statement" id="st-d0_s18" data-properties="corolla coloration">corollas whitish [yellow] (tubes longer than ± campanulate throats, lobes 5, erect or recurved, lanceolate to linear; styles linear to clavate, branches usually 0 or short-conic and papillate, sometimes lanceolate to oblong and ± hispidulous).</span> <span class="statement" id="st-d0_s19" data-properties="cypsela shape;cypsela architecture or shape;cypsela architecture or shape;face pubescence"><b>Cypselae </b>narrowly cylindric to weakly fusiform or ± prismatic, 5-ribbed or 10-ribbed, faces glabrous [villous];</span> <span class="statement" id="st-d0_s20" data-properties="bristle quantity;bristle coloration;bristle architecture;bristle architecture">pappi (pistillate florets) readily falling or fragile, of 60–100+, white, smooth or barbellulate bristles (elongating in fruit).</span> <span class="statement" id="st-d0_s21" data-properties="pappus life cycle;pappus fragility;x chromosome quantity">x = 30.</span><!-- -->{{Treatment/Body |distribution=Boreal North America;southward in w Cordillera;Eurasia |discussion=<p>Species 15–18 (1 in the flora).</p><!-- --><p>North American Petasites is taxonomically difficult as a result of low variability in reproductive morphology and a high degree of leaf polymorphism. The conservative reproductive structures across all taxa make identification almost impossible without foliage and, unhappily, flowering usually occurs prior to emergence of basal leaves. Further compounding the taxonomic confusion is the apparent intergradation of many of the different leaf forms as well as leaf morphologies being subject to environmental plasticity.</p><!-- --><p>Using morphometric, isozymic, and chromosomal data as well as crossing studies and observations of field and herbarium specimens, relationships of the various entities have been interpreted by D. M. Cherniawsky and R. J. Bayer (1998, 1998b). North American Petasites has been shown to be loosely comprised of four polymorphic groups. Close relationships among the groups were evident in all analyses by Cherniawsky and Bayer and suggested rapid and recent morphologic and genetic divergence in North America. They postulated that groups within North American Petasites have not yet reached a level of differentiation characteristic of distinct species. On this basis, North American Petasites is treated here as one polymorphic species with four infraspecific taxa, one a hybrid.</p><!-- --><p>Characters used in this treatment are those found to be the most taxonomically discriminating by D. M. Cherniawsky and R. J. Bayer (1998c), although there is a high degree of overlap of ranges across all taxa. Morphologic variation is continuous for most reproductive characters. Values for reproductive characters are mostly continuous with only a few extreme ranges providing some taxonomic demarcation. Although leaf characters were shown to be the most reliable, it is recommended that a combination of both flowers and leaves be used for accurate identifications.</p><!-- --><p>In cooler regions of the northern hemisphere, Petasites glacialis and P. gmelinii, both with yellow corollas and 1[–3] heads per array, approach the Bering Strait in northeastern Siberia; they apparently do not reach Alaska (E. Hultén 1968).</p><!-- --><p>Two relatively large-leaved exotic species of Petasites are sold as ornamentals: the European P. hybridus (Linnaeus) Gaertner, Meyer, & Scherbius, with purplish florets and reniform to orbiculate-cordate, shallowly angular-lobed, finely and unevenly toothed leaf blades 10–90(–100) cm wide; and the Asian P. japonicus (Siebold & Zuccarini) Maximowicz, with creamy white to whitish corollas and reniform-cordate, unlobed, finely toothed leaf blades 15–30(–150) cm wide. They occasionally escape cultivation (e.g., P. hybridus established in Michigan).</p><!-- --><p>The rhizomes, petioles, leaf blades, and young flower stalks of some species of Petasites are (or have been) used for food in various ways and their ashes are used as a salt substitute. In folk medicine, some species of Petasites are used as antiasthmatics, antispasmodics, and expectorants and in salve or poultice form.</p><!-- --><p>Measurements in the following key leads and descriptions are based almost wholly on North American specimens.</p> |tables= |references={{Treatment/Reference |id=cherniawsky1998a |text=Cherniawsky, D. M. and R. J. Bayer. 1998. Systematics of North American Petasites (Asteraceae: Senecioneae). I. Morphometric analyses. Canad. J. Bot. 76: 23–36. }}{{Treatment/Reference |id=cherniawsky1998b |text=Cherniawsky, D. M. and R. J. Bayer. 1998b. Systematics of North American Petasites (Asteraceae: Senecioneae). II. Isozyme analysis and population genetic structure. Canad. J. Bot. 76: 1476–1487. }}{{Treatment/Reference |id=cherniawsky1998c |text=Cherniawsky, D. M. and R. J. Bayer. 1998c. Systematics of North American Petasites (Asteraceae: Senecioneae). III. A taxonomic revision. Canad. J. Bot. 76: 2061–2075. }}{{Treatment/Reference |id=toman1972a |text=Toman, J. 1972. A taxonomic survey of the genera Petasites and Endocellion. Folia Geobot. Phytotax. 7: 381–406. }} }}<!-- --><!-- -->{{#Taxon: name=Petasites |author=Randall J. Bayer;A. Linn Bogle;Donna M. Cherniawsky |authority=Miller |rank=genus |parent rank=tribe |synonyms= |basionyms= |family=Asteraceae |distribution=Boreal North America;southward in w Cordillera;Eurasia |reference=cherniawsky1998a;cherniawsky1998b;cherniawsky1998c;toman1972a |publication title=Gard. Dict. Abr. ed. |publication year=1754 |special status= |source xml=https://bibilujan@bitbucket.org/aafc-mbb/fna-fine-grained-xml.git/src/84153f6d59a0a91d69695978a64cee7560374f8e/V19-20-21/V20_1434.xml |tribe=Asteraceae tribe Senecioneae |genus=Petasites |abaxial face pubescence=tomentose |adaxial leaf pubescence=glabrous;glabrescent;tomentulose |array architecture=racemiform;paniculiform;corymbiform |basal leaf architecture=nerved |basal leaf shape=mostly deltate;ovate or orbiculate |bractlet quantity=1;5 |bristle architecture=barbellulate;smooth |bristle coloration=white |bristle quantity=60;100 |calyculus presence=absent |calyculus quantity=of 1;5+ bractlets |cauline leaf shape=bractlike |corolla coloration=whitish;pinkish;purplish |cypsela architecture or shape=10-ribbed;5-ribbed |cypsela shape=narrowly cylindric;weakly fusiform or more or less prismatic |face pubescence=glabrous |head architecture or arrangement=radiate |head architecture or shape=disciform;discoid |head arrangement=singly |inner floret architecture=staminate |inner floret quantity=1;78 |inner floret reproduction=fertile;bisexual |involucre diameter=6mm;15mm |involucre shape=obconic;turbinate |leaf architecture=sessile;petiolate |leaf arrangement=alternate |leaf position=cauline;basal |margin shape=toothed;lobed |margin texture=scarious |pappus fragility=fragile |pappus life cycle=falling |peripheral floret presence=absent |peripheral floret quantity=30;125 |peripheral floret reproduction=fertile |phyllarie duration=persistent |phyllarie fusion=connate;distinct |phyllarie orientation=erect |phyllarie quantity=12;15 |phyllarie shape=narrowly oblong;linear |phyllarie size=subequal |ray-floret architecture=neuter;styliferous |ray-floret atypical quantity=1;30 |ray-floret presence=absent |ray-floret quantity=30;130 |ray-floret reproduction=sterile;fertile |receptacle architecture=epaleate |receptacle relief=foveolate |receptacle shape=flat;convex |series atypical quantity=1;2 |series quantity=2 |stem architecture=not branched |stem orientation=erect |whole-organism atypical some measurement=25cm;120cm |whole-organism duration=perennial |whole-organism some measurement=10cm;25cm |x chromosome quantity=30 }}<!-- -->[[Category:Treatment]][[Category:Asteraceae tribe Senecioneae]] Templates used on this page: Template:Asteraceae (view source) Template:Treatment/AuthorLink (view source) Template:Treatment/Body (view source) Template:Treatment/Body/Maps (view source) Template:Treatment/ID (view source) Template:Treatment/Publication (view source) Template:Treatment/Reference (view source) Return to Petasites.