Packera streptanthifolia |
Packera antennariifolia |
|
---|---|---|
cleft-leaf groundsel, Rocky Mountain butterweed, Rocky Mountain groundsel |
shale barren ragwort |
|
Habit | Perennials, 10–50+ cm; fibrous-rooted (caudices weak to stout, horizontal to suberect). | Perennials, 20–40+ cm; rhizomatous (rhizomes branched, horizontal to suberect). |
Stems | 1 or 2–5, clustered, usually glabrous, sometimes sparsely floccose-tomentose proximally and in leaf axils. |
1 (sometimes from rosettes, rosettes sometimes clustered), tomentose. |
Basal leaves | (and proximal cauline, relatively thick and turgid) petiolate; blades spatulate to oblanceolate, or ovate to orbiculate, 20–40+ × 10–30+ mm, bases tapering to abruptly contracted or subcordate, margins entire, crenate, dentate, or weakly lobulate (faces usually glabrous, sometimes hairy). |
petiolate; blades broadly lanceolate to elliptic or spatulate, 20–40+ × 10–20+ mm, bases tapering, margins entire or subentire to dentate distally (faces tomentose). |
Cauline leaves | gradually to abruptly reduced (± petiolate or sessile; entire or subentire). |
abruptly reduced (petiolate or sessile; narrowly lanceolate to sublyrate, sharply toothed to pinnatisect or entire). |
Peduncles | bracteate, glabrous or sparsely tomentose. |
bracteate, densely lanate to sparsely tomentose. |
Ray florets | 8 or 13; corolla laminae 5–10 mm. |
8–10(–13); corolla laminae 5–10 mm. |
Disc florets | 35–60+; corolla tubes 2–4 mm, limbs 2.5–4 mm. |
25–35+; corolla tubes 3–4 mm, limbs 1.5–2 mm. |
Phyllaries | (8–)13 or 21, green (tips sometimes cyanic), 4–7+ mm, glabrous. |
13 or 21, green, 5–7 mm, densely tomentose (apices scarious). |
Calyculi | conspicuous. |
inconspicuous. |
Heads | 2–20+ in loose, corymbiform or subumbelliform arrays. |
6–12+ in corymbiform arrays (lateral cymiform arrays sometimes originating in leaf axils). |
Cypselae | 1–2.5 mm, glabrous; pappi 3–6 mm. |
1–1.5 mm, hirtellous on ribs; pappi 4–5 mm. |
2n | = 46, 92. |
= 46. |
Packera streptanthifolia |
Packera antennariifolia |
|
Phenology | Flowering late May–late Aug. | Flowering late Apr–late May. |
Habitat | Forests, open meadows, valleys, dry to damp and loamy soils | Slopes on shale barrens |
Elevation | 1000–3400 m (3300–11200 ft) | 300–800 m (1000–2600 ft) |
Distribution |
CA; CO; ID; MT; NM; NV; OR; UT; WA; WY; AB; BC; NT; SK; YT
|
MD; PA; VA; WV |
Discussion | Packera streptanthifolia is widespread and variable throughout the Western Cordillera. It includes weakly defined phases that have been treated as distinct species or as varieties. Characteristics used to delimit those taxa often overlap and are difficult to score; some “phases” grade into each other. Northern populations are sometimes segregated as a distinct taxon (e.g., Senecio streptanthifolia var. borealis; J. F. Bain 1988). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Packera antennariifolia is known only from shale barrens or shale-derived soils in central Appalachia. Plants growing on steep slopes have stouter, more horizontal caudices and more extensive fibrous roots than specimens from other locations. Specimens from shale-derived soils, not growing directly on shale barrens, have weakly lobulate leaves and noticeably less hairiness. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 599. | FNA vol. 20, p. 578. |
Parent taxa | Asteraceae > tribe Senecioneae > Packera | Asteraceae > tribe Senecioneae > Packera |
Sibling taxa | ||
Synonyms | Senecio streptanthifolius, P. streptanthifolia var. borealis, Senecio adamsii, Senecio aureus var. borealis, Senecio cognatus, Senecio cymbalarioides, Senecio cymbalarioides var. borealis, Senecio cymbalarioides var. streptanthifolius, Senecio fulgens, Senecio jonesii, Senecio leonardii, Senecio longipetiolatus, Senecio oödes, Senecio platylobus, Senecio rydbergii, Senecio streptanthifolius var. borealis, Senecio streptanthifolius var. kluanei, Senecio streptanthifolius var. laetiflorus, Senecio streptanthifolius var. oödes, Senecio streptanthifolius var. rubricaulis, Senecio streptanthifolius var. wallowensis, Senecio subcuneatus, Senecio suksdorfii, Senecio wardii | Senecio antennariifolius |
Name authority | (Greene) W. A. Weber & Á. Löve: Phytologia 49: 48. (1981) | (Britton) W. A. Weber & Á. Löve: Phytologia 49: 45. (1981) |
Web links |