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Crepis atribarba

(Hawksbeard)

Overview

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Interesting Facts

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Common Names

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Common Names in English:

Hawksbeard, Dark Hawksbeard, Slender Hawksbeard

Description

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Family Compositae

The largest family of flowering plants , the Compositae (Asteraceae), comprising about 1,100 genera and more than 20,000 species and characterized by many small flowers arranged in a head looking like a single flower and subtended by an involucre of bracts. A head may consist of both ray flowers and disk flowers, as in the sunflower, of disk flowers only, as in the burdock, or of ray flowers only, as in the dandelion.

Tribe Lactuceae

The Lactuceae are a tribe of closely related genera of the sunflower family that are easily recognized because the flowering heads are composed of wholly of ligulate florets that are usually 5-lobed. Another very distinguishing feature is the milky sap . Although not apparent without magnification, the pollen is distinctive in that the spines are more or less restricted to discrete ridges or flanges on the surface of the grain. In other members of the family the spines are distributed more or less evenly over the surface of the pollen grain . The pappus usually consists of scales or stiff hairs . -- Gerald D. Carr.

Genus Crepis

Annuals , biennials, or perennials , 3-120 cm; usually taprooted, sometimes rhizomatous (roots deep or shallow, woody or fibrous , caudices often woody). Stems 1-20+. erect to decumbent . simple (sometimes scapiform ) or branched, usually striate , glabrous or hairy , often densely hispid or setose (hairs often stipitate-glandular ). Leaves basal (often in rosettes) and cauline; petiolate (at least basal, petioles ± winged ) ; basal blades mostly elliptic , ovate , or lanceolate to linear , or spatulate to oblanceolate , often lyrate or runcinate, margins entire, dentate , serrate, toothed , or pinnately lobed , lobes sometimes toothed; cauline usually present, lobed or entire, usually reduced in size and lobing distally. Heads (erect) usually in cymiform, corymbiform , or paniculiform arrays, sometimes borne singly. Peduncles not inflated distally, not bracteate . Calyculi of 5-12, reduced, subulate to lanceolate or deltate bractlets in ± 1 series, mostly unequal, glabrous, tomentulose , or setose. Involucres cylindric to campanulate (sometimes becoming turbinate in fruit), 4-15 mm diam. Phyllaries 5-18 in 1-2 series. lanceolate, equal or subequal , (bases becoming thickened and keeled , keels sometimes pronounced in fruit) margins green to yellowish, often scarious , apices acute to acuminate, abaxial faces glabrous, tomentose , or setose, sometimes stipitate-glandular, adaxial glabrous or with appressed hairs. Receptacles flat or convex , usually pitted , glabrous or hairy, epaleate [paleate, paleae narrow, thin]. Florets 5-100+; corollas usually yellow or orange, sometimes white, pink, or reddish. Cypselae monomorphic or dimorphic . yellow, brown, green, red, and/or black, subcylindric or fusiform , terete or subterete, usually curved , apices tapered or beaked , ribs 10-20, sometimes spiculate-roughened, faces glabrous or hispidulous ; pappi persistent or falling, of 80-150, usually distinct , sometimes basally connate , white to tawny , coarse to fine, ± equal (or outer shorter), barbellulate bristles in 1-2 series. x = 3, 4, 5, 6, 11.

Species ca. 200: North America, Eurasia , Africa; introduced nearly worldwide.

Crepis is generally recognized by the rosettes of coarse, often pinnately lobed leaves, erect heads, epaleate receptacles, calyculate involucres. yellow corollas, subcylindric or fusiform, ribbed cypselae, and pappi of barbellulate bristles. The taxonomy and evolutionary relationships of Crepis were studied by E. B . Babcock (1947) and his associates. Their work was thorough and important because of the effort to incorporate cytogenetic information in the evolutionary analysis. Extensive survey of chromosome number and karyotype indicated two major ploidy groups in Crepis, corresponding to New World and Old World species complexes. Of the 12 species of Crepis native to North America, 10 are polyploids with x = 11. The core diploid populations commonly occupy discrete ecologic zones and are thought to be entirely distinct from one another, yet they are interconnected by a continuous complex series of intergrading polyploid forms that are partly or completely apomictic (Babcock). The polyploids are of two forms, autopolyploids that are similar to the diploids, and allopolyploids that combine the characteristics of two or more diploid species. The allopolyploid forms of hybrid origin may exhibit the characteristics of multiple parental species and therefore are difficult to classify. Some of the heterogeneous apomictic populations, or groups of populations, have been grouped together and recognized as subspecies ; those taxa are often difficult to identify and further study is clearly needed. Despite these difficulties, the subspecific taxa of Babcock were tentatively included in the present study. The Old World species are mostly diploid (n = 3, 4, 5, or 6). Babcock concluded that there was a progressive decrease in the chromosome numbers, from n = 6 to n = 3. Along with the decrease is a corresponding increase in chromosome asymmetry and reduction in chromosome length.[1]

Physical Description

Species Crepis atribarba

Perennials , 15-70 cm (taproots slender, caudices swollen, often covered by old leaf bases ). Stems 1-2, erect , slender, usually branched distal to middles , glabrous or tomentulose . Leaves basal and cauline; petiolate ; blades lanceolate to linear , 10-35 × 0.5-6 cm, margins deeply pinnately lobed (lobes narrowly lanceolate or linear, usually entire or toothed ), apices acuminate, faces tomentulose to glabrate . Heads 3-30, in corymbiform arrays. Calyculi of 5-10, narrowly triangular to lanceolate, tomentose bractlets 1-3 mm. Involucres cylindro-campanulate, 10-12 × 4-7 mm. Phyllaries 8-13, lanceolate, 10-12 mm (margins yellow, scarious , eciliate ), apices acute, abaxial faces usually tomentulose, sometimes glabrous, often with coarse , green or blackish setae, adaxial glabrous or with fine, appressed hairs . Florets 6-35; corollas yellow, 10-18 mm. Cypselae dark or blackish green, subcylindric , 3-10 mm, apices tapered, not beaked , ribs 12-15 (distinct ) ; pappi whitish, 5-9 mm. 2n = 22, 33, 44, 55, 88. [source]

Crepis atribarba is generally recognized by the deeply pinnately lobed leaves with linear lobes, fine tomentulose indument on stems and leaves, setose phyllaries, and dark green, strongly ribbed cypselae. It is a variable mixture that includes polyploid, apomictic forms and hybrids with C. acuminata and other species. The typical form is recognized by its short stature, narrow pinnately lobed, tomentulose leaves, stems with 3-10 heads , and phyllaries with scattered , black, eglandular setae. Larger, more robust forms with stems 30-70 cm, 10-30+ heads, narrower involucres, and few or no black setae have been recognized as subsp. originalis. The latter was considered by E. B . Babcock (1947) to represent the original diploid form of the species; it is difficult to distinguish in practice. [source]

Habit: Forb/herb

Flowers: Bloom Period: May, June, July. • Flower Color: yellow

Habitat

Dry, open, grassy places, sagebrush slopes , pine forests , gravelly stream banks; 200-3000 m [2].

Biology

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Reproduction

Duration: Perennial

Growth

Sunlight: Sun Exposure: Full Sun .

Taxonomy

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Synonyms

C. exilis originalis Babcock & Stebbins • C. occidentalis Nuttall Var. gracilis D. C. Eaton • Crepis exilis Osterhout

Notes

Name Status: Accepted Name .

Comment: Data Providers: Govaerts World Compositae Checklist A-G, IPNI, Tropicos, LCR Editor. GCC LSID: urn :lsid:compositae.org:names:5787B390-7853-4DF6-B29F-503E66A28110

Last scrutiny: 18-Nov-09

Similar Species

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Members of the genus Crepis

ZipcodeZoo has pages for 44 species, subspecies, varieties, forms, and cultivars in this genus:

C. acuminata (Long-Leaf Hawksbeard) · C. acuminata acuminata (Longleaf Hawksbeard) · C. acuminata pluriflora (Longleaf Hawksbeard) · C. atribarba (Hawksbeard) · C. atribarba atribarba (Hawksbeard) · C. aurea (Golden Hawks Beard) · C. bakeri (Baker's Hawksbeard) · C. bakeri cusickii (Baker's Hawksbeard) · C. bakeri idahoensis (Baker's Hawksbeard) · C. biennis (Rough Hawksbeard) · C. bursifolia (Italian Hawksbeard) · C. capillaris (Smooth Hawk's-Beard) · C. elegans (Elegant Hawksbeard) · C. foetida (Roadside Hawksbeard) · C. foetida foetida (Stinking Hawksbeard) · C. intermedia (Gray Hawksbeard) · C. modocensis rostrata (Common Hawksbeard) · C. monticola (Mountain Hawksbeard) · C. nana (Dwarf Alpine Hawksbeard) · C. nana ramosa (Dwarf Alpine Hawksbeard) · C. nicaeensis (Turkish Hawksbeard) · C. occidentalis conjuncta (Gray Hawksbeard) · C. occidentalis pumila (Large-Flower Hawk's-Beard) · C. pannonica (Pasture Hawksbeard) · C. pleurocarpa (Naked-Stem Hawksbeard) · C. pulchra (Hawksbeard) · C. pulchra pulchra (Smallflower Hawksbeard) · C. pumila (Largeflower Hawksbeard) · C. rostrata (Modoc Hawksbeard) · C. rubra (Hawksbeard) · C. rubra 'Alba' (Hawks Beard) · C. runcinata andersonii (Dandelion Hawksbeard) · C. runcinata barberi (Barber's Hawksbeard) · C. runcinata hallii (Fiddleleaf Hawksbeard) · C. runcinata hispidulosa (Fiddleleaf Hawksbeard) · C. runcinata imbricata (Fiddleleaf Hawksbeard) · C. runcinata runcinata (Fiddle-Leaf Hawk's-Beard) · C. setosa (Bristly Hawksbeard) · C. tectorum (Narrow-Leaf Hawk's-Beard) · C. tectorum tectorum (Narrowleaved Hawk's Beard) · C. vesicaria (Beaked Hawksbeard) · C. vesicaria haenseleri (Beaked Hawksbeard) · C. vesicaria taraxacifolia (Beaked Hawksbeard) · C. zacintha (Striped Hawksbeard)

More Info

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Further Reading

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Notes

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Contributors

Data Sources

Accessed through GBIF Data Portal February 03, 2008:

Identifiers

Footnotes

  1. David J. Bogler "Crepis". in Flora of North America Vol. 19, 20 and 21 Page 214, 216, 217, 219, 222, 223, 228. Oxford University Press. Online at EFloras.org. [back]
  2. "Crepis atribarba". in Flora of North America Vol. 19, 20 and 21 Page 224, 225, 227, 229. Oxford University Press. Online at EFloras.org. [back]
Last Revised: 7/15/2012