|University of California, Berkeley|
|Directory News Site Map Home|
Key to families | Table of families and genera
Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.
Annual to subshrub. Stem: 1–several from taproot or ± branched caudex, generally branched distally and ± bushy. Leaf: alternate, entire to irregularly serrate or dentate, proximal tapered at base; teeth generally bristle-tipped. Inflorescence: heads generally radiate, in cyme-like clusters; involucre bell-shaped, hemispheric, or obconic; phyllaries in 3–12 series of unequal length, proximally straw-colored, distally green; receptacle convex, with short, triangular scales, glabrous, epaleate. Ray flower: (0)7–many; corolla white, blue, or purple. Disk flower: 15–generally many; corolla 5.5–8 mm, yellow; anther tip lanceolate; style tips lanceolate. Fruit: 2.5–3.5 mm, generally narrowly obovate, weakly curved and ± flattened, smooth or generally with 5–7 ribs on each face, glabrous or ± silky; pappus 6–8 mm, of many unequal bristles.
3 species: temperate western North America. (Greek: biennial, from duration of type sp.) [Morgan 2006 FNANM 20:395–401]
Unabridged references: [Morgan & Hartman 2003 Sida 20:1387–1416]
1. Ray flowers 0 ..... D. canescens var. shastensis (2)
1' Ray flowers present
2. Phyllary tips acute to long-acuminate, 1–6 mm; phyllaries generally hairy and/or glandular throughout ..... D. asteroides
3. Involucre hemispheric; phyllary tips long-acuminate, 3–6 mm; leaves of mid-stem serrate or minutely serrate ..... var. asteroides
3' Involucre widely obconic to ± hemispheric; phyllary tips acute to short-acuminate, 1–3 mm; leaves of mid-stem entire or nearly so ..... var. lagunensis
2' Phyllary tips acute to short-acuminate, 1–3 mm; phyllaries generally hairy and/or glandular only on green tips ..... D. canescens
4. Heads generally 14–20 mm; subshrub or long-lived perennial herb; e Peninsular Ranges (Santa Rosa Mtns) ..... var. ziegleri
4' Heads generally 6–12 mm; annual to short-lived perennial herb; widespread
5. Stems with stalked glands, occasionally also canescent-puberulent ..... var. leucanthemifolia
5' Stems canescent-puberulent, stalked glands sparse or lacking
6. Stems stiffly erect, <= 60 cm; branches many, stiff, spreading; heads many ..... var. incana
6' Stems various, generally smaller; branches generally fewer, more flexible, loosely spreading to ascending; heads few to many
7. Ray flowers with styles, fertile, well developed; involucre generally 8–12 mm; phyllaries generally in 5–10 series ..... var. canescens
7' Ray flowers without styles, sterile, often ± reduced; involucre 6–9 mm; phyllaries generally in 3–5 series ..... var. shastensis (2)
Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
We encourage links to these pages, but the content may not be downloaded for reposting, repackaging, redistributing, or sale in any form, without written permission from The Jepson Herbarium.