Jepson eFlora
Key to families | Table of families and genera

Key to Lactuca

View taxon page for Lactuca

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Fruit beak short, thick; biennial or perennial herb

2. Biennial from short taproot; open heads 1–1.5 cm diam; Northwestern California, n Central Coast ..... L. biennis

2' Perennial herb from long, deep rhizome; open heads 2–3 cm diam; High Cascade Range, c High Sierra Nevada, Modoc Plateau ..... L. tatarica subsp. pulchella

1' Fruit beak slender, thread-like; annual or biennial

3. Fruit 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' Fruit 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. Stems 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' Stems 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, [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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