Chrysothamnus Nuttall (Q2154)

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Chrysothamnus is a taxon with the rank genus within the tribe Astereae
Language Label Description Also known as
English
Chrysothamnus Nuttall
Chrysothamnus is a taxon with the rank genus within the tribe Astereae

    Statements

    taxon/id/Chrysothamnus Nuttall
    0 references
    Chrysothamnus Nuttall
    Chrysothamnus
    Nuttall
    FNA Editorial Committee. 2006. Flora of North America north of Mexico. Volume 20: Magnoliophyta: Asteridae, part 7: Asteraceae, part 2. Oxford University Press, New York.
    accepted
    rabbitbrush (English)
    Rabbitbrush (English)
    w North America
    Shrubs or subshrubs, 8–120 cm (often rounded, compact; usually with woody, often highly branched caudices).
    Stems ascending to erect or spreading (greenish when young, with age, bark tan to gray, flaky or fibrous), simple (branched in arrays, sometimes ridged from leaf-bases), glabrous, hairy, or stipitate-glandular, sometimes gland-dotted, often resinous.
    short-petiolate or sessile;
    blades with usually evident midnerves plus 0–2 pairs of fainter collateral nerves (secondary nerves raised and reticulate in C. eremobius), filiform, lanceolate, elliptic, or obovate (flat or sulcate, sometimes twisted or folded), margins entire, sometimes hirtellous to ciliate (apices usually acute, sometimes apiculate or spinulose), faces glabrous or hairy, sometimes gland-dotted, often resinous.
    Heads discoid (usually short-pedunculate), borne singly or in condensed cymiform clusters, these in usually paniculiform, corymbiform, rarely racemiform arrays.
    Involucres usually turbinate, obconic, or cylindric, sometimes hemispheric, (5–15 ×) 1.5–15 mm.
    Phyllaries 12–60+ in (2–) 3–7 series (in vertical ranks or spirals, tan, sometimes green and/or purplish subapically or along midveins), usually evidently 1-nerved (often keeled, sometimes flat to convex), linear to elliptic, lanceolate to ovate, or obovate to spatulate, unequal, chartaceous, outer sometimes herbaceous, margins scarious (entire, ciliolate to erose, apices acute to acuminate or rounded, sometimes apiculate to cuspidate or cupped), faces glabrous or hairy, often resinous.
    Receptacles convex, pitted, epaleate.
    Disc-florets 2–40+ (often 5–6);
    corollas yellow, tubes shorter than campanulate to funnelform throats, lobes 5, erect to spreading, triangular to lanceolate;
    style-branch appendages mostly attenuate.
    Cypselae (tan to reddish-brown) turbinate to elliptic or cylindric, sometimes ± flattened to 4–5-angled, often 5–10-ribbed, faces glabrous or densely hairy, sometimes glandular;
    pappi persistent, of 15–50+, tan, stramineous, or white, fine to coarse, barbellate, apically attenuate bristles in 1 series (of 12–15, white to stramineous, lanceolate or lance-linear scales in C. stylosus).