Packera glabella |
Packera tridenticulata |
|
---|---|---|
butterweed |
threetooth ragwort |
|
Habit | Annuals or biennials, 20–70+ cm; fibrous-rooted (caudices relatively short, weak). | Perennials, 10–30+ cm; taprooted (caudices ascending to erect). |
Stems | 1 (striated, frequently hollow, often pink- to purple-tinged), glabrous or leaf axils sparsely tomentose. |
1 or multiple, clustered, usually glabrous, rarely sparsely floccose-tomentose, leaf axils sometimes tomentose. |
Basal leaves | (and proximal cauline) obscurely petiolate; blades obovate to oblanceolate, sometimes lyrate (lateral lobes to 5 pairs, terminal lobes larger than laterals), 50–150+ × 10–30+ mm, bases tapering, ultimate margins crenate to irregularly undulate. |
(and proximal cauline, relatively thick and turgid) petiolate; blades lanceolate or narrowly oblanceolate, 20–40+ × 5–15 mm, bases tapering, margins usually entire, sometimes sub-pinnatisect (apices subentire or dentate). |
Cauline leaves | gradually reduced (weakly clasping, similar to basal). |
gradually reduced (± petiolate or sessile). |
Peduncles | bracteate, glabrous or bases tomentose. |
bracteate, glabrous or sparsely tomentose. |
Ray florets | (8–)13; corolla laminae 7–9 mm. |
8–10(–13); corolla laminae 5–8+ mm. |
Disc florets | 35–50+; corolla tubes 2.5–3.5 mm, limbs 2–3 mm. |
45–60+; corolla tubes 3–3.5 mm, limbs 4–5 mm. |
Phyllaries | (13–)21, green, 5–7 mm, glabrous. |
13 or 21, green, 6–10 mm, sparsely tomentose proximally, glabrous distally. |
Calyculi | conspicuous (bractlets 2.5–4 mm). |
inconspicuous. |
Heads | 8–30+ in umbelliform or cymiform arrays (robust plants with multiple arrays). |
4–15+ in corymbiform arrays. |
Cypselae | 1–1.5 mm, sparsely hirtellous on ribs or glabrous; pappi 3–4 mm. |
1.5–2.5 mm, glabrous or sparsely hirtellous on ribs; pappi 5–6 mm. |
2n | = 46. |
= 46. |
Packera glabella |
Packera tridenticulata |
|
Phenology | Flowering (Feb–)mid Mar–late May. | Flowering late May–early Jul. |
Habitat | Open wet areas, edges of woodlands, stream banks, roadsides, meadows, marshes, fallow fields | Open, dry areas, roadsides, gravelly or sandy slopes, short-grass prairies or sagebrush scrubs |
Elevation | 0–600 m (0–2000 ft) | 1000–2000 m (3300–6600 ft) |
Distribution |
AL; AR; FL; GA; IL; IN; KS; KY; LA; MO; MS; NC; NE; OH; OK; SC; TN; TX
|
CO; KS; ND; NE; NM; OK; SD; TX; WY
|
Discussion | Packera glabella is common and almost weedy in wet, partially shaded places. The hollow, striated stems of P. glabella are distinctive. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Packera tridenticulata is found throughout the central High Plains, in the foothills of the Rocky Mountains, and in high valleys to the west of the Rocky Mountain front. It tends to grow in clumps; the multiple stems arise from well-developed taproots. It apparently hybridizes with P. neomexicana var. mutabilis where their ranges overlap. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 20, p. 588. | FNA vol. 20, p. 601. |
Parent taxa | Asteraceae > tribe Senecioneae > Packera | Asteraceae > tribe Senecioneae > Packera |
Sibling taxa | ||
Synonyms | Senecio glabellus, Senecio carolinianus, Senecio densiflorus, Senecio lobatus, Senecio lyratus, Senecio mississipianus | Senecio tridenticulatus, Senecio acutidens, Senecio compactus, Senecio densus, Senecio oblanceolatus |
Name authority | (Poiret) C. Jeffrey: Kew Bull. 47: 101. (1992) | (Rydberg) W. A. Weber & Á. Löve: Phytologia 49: 48. (1981) |
Web links |