treatments/SAUSSUREA

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SAUSSUREA de Candolle Ann. Mus. Natl. Hist. Nat.. 16: 156, 196, plates 10–13. 1810.

Saw-wort [For Nicolas Théodore (1767–1845) and Horace Bénédict (1740–1799) de Saussure, Swiss naturalists]

David J. Keil,

Perennials, 5–120+ cm; herbage tomentose or glabrescent, not spiny. Stems erect or ascending, simple or branched. Leaves basal or cauline (sometimes cauline only), sessile or petiolate; blade margins entire or dentate to pinnately lobed, faces glabrous to densely tomentose, glandular or eglandular. Heads discoid, borne singly or in corymbiform arrays. Involucres ovoid to campanulate or ± turbinate. Phyllaries many in 3–5(–10+) series, subequal to strongly unequal, appressed or not, ovate to lanceolate, margins entire, toothed, or lobed, apices obtuse or acute, appendaged or not, not spine-tipped. Receptacles flat or convex, epaleate, smooth, usually subulate-scaly, sometimes bristly or naked. Florets 10–20; corollas white to blue or purple, tubes slender, abruptly expanded to throats, lobes linear; anther bases short-tailed, apical appendages linear, acute; style branches: fused portions with minutely hairy subterminal nodes, distinct portions oblong to linear, short-papillate. Cypselae oblong, ± angled, cylindric or 4–5-angled, ribs (when present) smooth or roughened, apices entire, glabrous or minutely glandular, attachment scars basal; pappi usually of 2 series, outer of readily falling, short bristles, inner persistent or falling as unit, of basally connate, usually longer, plumose bristles. x = 13, 14, 16, 17, 18, 19?.


Species 300–400 (6 in the flora):North America; Eurasia; 1 in Australia.;

Saussurea is a notoriously difficult, largely Asiatic genus with species boundaries often indistinct.
SELECTED REFERENCES
Lipschitz, S. J. 1979. Rod Saussurea DC. (Asteraceae). Leningrad.


1. Outer and mid phyllaries with toothed or lobed appendages 6. Saussurea amara
1. Outer and mid phyllaries entire, without appendages. (2.)
2. Proximal leaves ovate to lanceolate, usually more than 30 mm wide, bases broadly obtuse to truncate or cordate; plants 30–120 cm. (3.)
3. Cauline leaves usually more than 20, finely to ± coarsely serrate or dentate; s Alaska and Yukon to California, Idaho, and Montana 1. Saussurea americana
3. Cauline leaves usually 15 or fewer, coarsely laciniate-dentate; nw Alaska 2. Sausserea triangulata
2. Proximal leaves linear to elliptic, 2–25 mm wide, bases acute to acuminate; plants 3–40 cm. (4.)
4. Phyllaries subequal, linear to lanceolate; receptacles naked 4. Saussurea nuda
4. Phyllaries strongly unequal, the outer ovate to lanceolate, conspicuously shorter than inner; receptacles scaly. (5.)
5. Tips of outer and mid phyllaries acute; Alaska and nw Canada 3. Saussurea angustifolia
5. Tips of outer and mid phyllaries ± rounded; Rocky Mountains 5. Saussurea weberi