Jepson eFlora
Key to families | Table of families and genera

Key to Lactuca

View taxon page for Lactuca

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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