Packera plattensis |
Packera indecora |
|
---|---|---|
plains butterweed, prairie groundsel |
elegant groundsel, rayless mountain butterweed, rayless mountain groundsel, rayless mountain ragwort |
|
Habit | Biennials or perennials, 20–60+ cm; rhizomatous and/or fibrous-rooted (bases erect to suberect), sometimes stoloniferous (mostly eastern populations). | Perennials, 10–100 cm; taprooted (caudices erect to suberect, relatively stout, branched). |
Stems | 1 or 2–3, clustered, floccose-tomentose proximally and in leaf axils, otherwise sparsely tomentose or glabrescent. |
1 or 2–3, loosely clustered, glabrous or glabrate. |
Basal leaves | (and proximal cauline) petiolate; blades narrowly elliptic to elliptic-ovate or oblanceolate to suborbiculate or sublyrate, 20–70+ × 10–30+ mm, bases tapering to rounded or abruptly contracted, margins subentire to crenate, serrate-dentate, or pinnately lobed (abaxial faces floccose-tomentose, especially along midribs, ± glabrescent). |
petiolate; blades elliptic-ovate, oblong, or subreniform, 20–50 × 10–40+ mm, bases subcordate, truncate, or cuneate, margins usually crenate-dentate to coarsely dentate-lacerate, seldom subentire. |
Cauline leaves | gradually reduced (petiolate, sublyrate or pinnatisect, abaxial faces sparsely hairy; distals sessile, subentire to irregularly dissected). |
gradually reduced (petiolate, resembling basals, sublyrate or dissected; distal sessile, subentire to pinnatifid). |
Peduncles | conspicuously bracteate, sparsely to densely tomentose. |
ebracteate (or bractlets inconspicuous), glabrous or glabrate. |
Ray florets | 8–10; corolla laminae 9–10 mm. |
0 or 8–10; corolla laminae (deep yellow) 3–5 mm. |
Disc florets | 60–70+; corolla tubes 2.5–3.5 mm, limbs 3.5–4.5 mm. |
60–70+; corolla tubes 2–3 mm, limbs 2.5–3.5 mm. |
Phyllaries | 13 or 21, green (tips sometimes cyanic), 5–6+ mm, densely tomentose proximally, glabrescent distally. |
13 or 21, green (tips sometimes reddish), 7–9 mm, glabrous. |
Calyculi | inconspicuous. |
conspicuous (bractlets green, tips sometimes reddish). |
Heads | 6–20+ in open or congested, corymbiform arrays. |
8–20+ in subumbelliform arrays. |
Cypselae | 1.5–2.5 mm, usually hirtellous, sometimes glabrous; pappi 6.5–7.5 mm. |
1–2 mm, glabrous; pappi 3–4 mm. |
2n | = 46, 92. |
= 46, 126, 176, 184. |
Packera plattensis |
Packera indecora |
|
Phenology | Flowering mid Apr–early Jun(–mid Jul, north). | Flowering mid Jun–late Aug. |
Habitat | Prairies, meadows, open wooded areas, along highways, railroads, around mining and construction areas, usually on limestone | Damp meadows, along streams, wet woodlands |
Elevation | 50–1800 m (200–5900 ft) | 0–2300 m (0–7500 ft) |
Distribution |
AR; CO; GA; IA; IL; IN; KS; LA; MI; MN; MO; MS; MT; ND; NE; NM; OH; OK; PA; SD; TN; VA; WI; WY; ON; SK
|
AK; CA; ID; MI; MN; MT; WA; WY; AB; BC; LB; MB; NT; NU; ON; QC; SK; YT
|
Discussion | Packera plattensis is abundant, widespread, and almost weedy. Putative hybrids with other species are known. Plants in mesic, remnant prairies in the east are sometimes stoloniferous. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Packera indecora is found at relatively low elevations in eastern Canada and at middle to subalpine elevations in the western cordillera. It closely resembles P. pauciflora and it is often difficult to identify specimens in the herbarium. Biosystematic studies (J. F. Bain and J. Whitton 1994) have indicated that although they are morphologically similar, P. indecora and P. pauciflora have distinctly different physiologies and should be maintained as distinct taxa. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 596. | FNA vol. 20, p. 590. |
Parent taxa | Asteraceae > tribe Senecioneae > Packera | Asteraceae > tribe Senecioneae > Packera |
Sibling taxa | ||
Synonyms | Senecio plattensis, Senecio pseudotomentosus | Senecio indecorus, Senecio burkei, Senecio idahoensis, Senecio pauciflorus subsp. fallax |
Name authority | (Nuttall) W. A. Weber & Á. Löve: Phytologia 49: 48. (1981) | (Greene) Á. Löve & D. Löve: Bot. Not. 128: 520. (1976) |
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