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Key to families | Table of families and genera
This text currently parallels The Jepson Manual: Vascular Plants of California, Second Edition that is now available at the University of California Press.
Text appearing in blue on this page will not appear in the printed book; it will be displayed only on the Web. 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 perennial herb; sap milky.
Stem: decumbent to erect.
Leaf: basal and cauline, alternate, entire to pinnately lobed.
Inflorescence: heads liguliflorous, in panicle-like or flat-topped clusters; involucre ± cylindric; phyllaries in 2–several series; receptacle flat or rounded, epaleate.
Flower: 6–50+; ligules yellow or cream to blue, readily withering.
Fruit: flattened, short- or long-beaked; pappus of 80–120+ bristles, falling separately.
± 100 species: ± worldwide temperate. (Latin: milky) [Strother 2006 FNANM 19:258–263] Lactuca sativa L. (garden lettuce) occasionally escapes from cultivation but does not persist.
1. Fr beak short, thick; biennial or perennial herb
2. Biennial from short taproot; open heads 1–1.5 cm diam; NW, n CCo ..... L. biennis
2' Perennial from long, deep rhizome; open heads 2–3 cm diam; CaRH, c SNH, MP ..... L. tatarica subsp. pulchella
1' Fr beak slender, thread-like; annual or biennial
3. Fr with 1 median rib on each face
4. Open heads 5–10 mm diam; flowers 13–25 ..... L. canadensis
4' Open heads 4–5 mm diam; flowers 20–56 ..... L. ludoviciana
3' Fr with 5–9 ribs on each face
5. Biennial; basal rosette leaves toothed or shallowly lobed; cauline leaves widely clasping ..... L. virosa
5' Annual; basal leaves generally 0 at flower; cauline leaves with narrow, acute, basal lobes clasping stem
6. Sts proximally decumbent and arching upward or erect, 5–10(20) dm; leaves lance-linear, entire or few-lobed, lobes linear; peduncles and inflorescence branches often appressed to axis; flowers 5–12 ..... L. saligna
6' Sts erect, 5–30 dm; leaves oblanceolate to oblong-elliptic or obovate in outline, margins prickly-toothed, sometimes also coarsely lobed; inflorescence branches often widely spreading; flowers 14–20 ..... L. serriola
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].
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