Kingdom: Plantae

Phylum: Magnoliophyta -- flowering plants

Class: Magnoliopsida -- dicots

Order: Asterales

Family: Asteraceae -- sunflower

Common Name: slender hawksbeard

Species Code: CRAT

Origin: Native to dry open places east of the Cascade Mountains from southern British Columbia to Oregon and east to Montana, Wyoming, Utah, and Nevada.

Rare: no

Form: forb, perennial from a taproot and a caudex, 15-70 cm tall, grey-tomentulose overall when young, becoming glabrate with age, sap milky.

Duration: perennial

Habitat Type: prairie

Wetland Indicator Status: not listed

Leaves: basal or alternate, grey-tomentulose when young becoming glabrate with age; basal and lower cauline leaves long petiolate, deeply divided into linear or lanceolate segments, upper leaves linear and entire.

Mature height: 6-26 inches

Flowers: all ligulate and perfect, yellow; involucre cylindrical, 8-15 mm high, grey-tomentulose and often with glandless black bristles.

Flower color: yellow

Bloom: May, June, July

Bloom starts on: late May

Bloom ends on: early July

Fruit: achene, ribbed, 3-10 mm long, greenish; pappus of copious capillary bristles, white or off-white.

Characteristics:
C. atribarba is considered the correct spelling and C. atrabarba an orthographic variant.
C. atrabarba in Hitchcock et al 1969, Hitchcock & Cronquist 1973. C. atribarba in St. John 1963, Davis 1953. C. gracilis(?) in Piper & Beattie 1914.
Reproduces sexually by seed
Perennating organ is a caudex.
Taprooted.
ssp. atrabarba is polyploid and usually apomictic while ssp. originalis may be diploid or polyploid and generally is not apomictic (Hitchcock et al 1969, Davis 1953).
Fruit is an achene.
Seeds are windborne.

Sun requirement: full sun

Soil moisture: xeric

Sowing time: probably should be fall sown

Transplant time: spring

Stratification: probably needs cold moist stratification

Seed yield: no information available

Seed harvest: difficult

Seed first harvest: no information available

Seed cleaning: no information available

Planting duration: no information available

Seed insect problem: no information available

Seed shatter: high

Seed size: small

Seed harvest date: late June, July

Seed comments: plants flower and ripen seed indeterminately and ripe seed is windborne. Frequent hand collection is needed

Herbaria: Specimen data and digital resources from The Consortium of Pacific Northwest Herbaria

Key words: forb upland

Propagation:
No information is available.
Preliminary results from the USDA NRCS Pullman Plant Materials Center suggests that cold moist stratification is helpful.
Reproduces sexually by seed

Notes: There are several Crepis species locally and any of them should be good landscaping plants for dry sites. We haven’t done anything with them yet. Common name is hawksbeard (Skinner et al 2005).

References:
Davis, Ray J. 1952. Flora of Idaho. Wm. C. Brown, Dubuque, Iowa. 827 pp.

Hitchcock, C. Leo, and Arthur Cronquist. 1973. Flora of the Pacific Northwest. Univ. of Washington Press. Seattle, WA.

Hitchcock, C. Leo, Arthur Cronquist, Marion Ownbey, and J.W. Thompson. 1969. Vascular Plants of the Pacific Northwest. University of Washington Press. Seattle, WA. 5 vol.

Piper, C.V., and R.K. Beattie. 1914. The Flora of Southeastern Washington and Adjacent Idaho. Lancaster, PA: Press of the New Era Printing Company. 296 pp.

Skinner, David M., Paul Warnick, Bill French, and Mary Fauci. 2005. More Palouse Forbs for Landscaping. USDA NRCS Pullman Plant Materials Center and Palouse Prairie Foundation. Online at http://www.wsu.edu/pmc_nrcs/Docs/More_Forbs_for_Landscaping.pdf

St. John, Harold. 1963. Flora of Southeastern Washington and of Adjacent Idaho. 3rd edition. Outdoor Pictures. Escondido, CA.

Links:
Plant Profile from the USDA PLANTS Database
Species description from Flora of North America
Species information from the University of Washington Herbarium