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butterweed

Small's ragwort

Habit Annuals or biennials, 20–70+ cm; fibrous-rooted (caudices relatively short, weak). Perennials, 30–70+ cm; fibrous-rooted (caudices erect to ascending).
Stems

1 (striated, frequently hollow, often pink- to purple-tinged), glabrous or leaf axils sparsely tomentose.

1 or 2–5, loosely clustered, bases densely tomentose, leaf axils usually 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.

petiolate;

blades narrowly elliptic to oblanceolate, 30–90+ × 10–20+ mm, bases tapering, margins serrate to crenate-serrate (apices rounded to acute, faces glabrous).

Cauline leaves

gradually reduced (weakly clasping, similar to basal).

gradually reduced (petiolate or sessile; elliptic to lanceolate, often pinnatifid).

Peduncles

bracteate, glabrous or bases tomentose.

bracteate, distally tomentose.

Ray florets

(8–)13;

corolla laminae 7–9 mm.

8 or 13;

corolla laminae 5–7+ mm.

Disc florets

35–50+;

corolla tubes 2.5–3.5 mm, limbs 2–3 mm.

45–60+;

corolla tubes 1.5–2 mm, limbs 1.5–2 mm.

Phyllaries

(13–)21, green, 5–7 mm, glabrous.

13 or 21, light green, 3–5 mm, glabrous.

Calyculi

conspicuous (bractlets 2.5–4 mm).

inconspicuous.

Heads

8–30+ in umbelliform or cymiform arrays (robust plants with multiple arrays).

20–70(–100+) in corymbiform arrays.

Cypselae

1–1.5 mm, sparsely hirtellous on ribs or glabrous;

pappi 3–4 mm.

0.75–1 mm, hirsute on ribs;

pappi 2.5–3 mm.

2n

= 46.

= 44.

Packera glabella

Packera anonyma

Phenology Flowering (Feb–)mid Mar–late May. Flowering early Jun–mid Jul (north), early Apr–late May (south).
Habitat Open wet areas, edges of woodlands, stream banks, roadsides, meadows, marshes, fallow fields Open fields, meadows, roadsides, disturbed sites, in drying or sandy soils
Elevation 0–600 m (0–2000 ft) 50–1800 m (200–5900 ft)
Distribution
from FNA
AL; AR; FL; GA; IL; IN; KS; KY; LA; MO; MS; NC; NE; OH; OK; SC; TN; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DC; FL; GA; KY; LA; MD; MS; NC; NY; OH; PA; SC; TN; VA; WV
[WildflowerSearch map]
[BONAP county map]
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 anonyma is common, almost weedy throughout most of its range. It grows on serpentine in Maryland, Ohio, and Pennsylvania. In western parts of its range, putative hybrids between P. anonyma and P. plattensis and P. tomentosa have been reported.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 20, p. 588. FNA vol. 20, p. 578.
Parent taxa Asteraceae > tribe Senecioneae > Packera Asteraceae > tribe Senecioneae > Packera
Sibling taxa
P. anonyma, P. antennariifolia, P. aurea, P. bernardina, P. bolanderi, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. greenei, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. paupercula, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. tridenticulata, P. werneriifolia
P. antennariifolia, P. aurea, P. bernardina, P. bolanderi, P. breweri, P. cana, P. cardamine, P. castoreus, P. clevelandii, P. contermina, P. crocata, P. cymbalaria, P. cynthioides, P. debilis, P. dimorphophylla, P. eurycephala, P. fendleri, P. flettii, P. franciscana, P. ganderi, P. glabella, P. greenei, P. hartiana, P. hesperia, P. hyperborealis, P. indecora, P. ionophylla, P. layneae, P. macounii, P. malmstenii, P. millefolium, P. millelobata, P. multilobata, P. musiniensis, P. neomexicana, P. obovata, P. ogotorukensis, P. pauciflora, P. paupercula, P. plattensis, P. porteri, P. pseudaurea, P. quercetorum, P. sanguisorboides, P. schweinitziana, P. spellenbergii, P. streptanthifolia, P. subnuda, P. tampicana, P. texensis, P. tomentosa, P. tridenticulata, P. werneriifolia
Synonyms Senecio glabellus, Senecio carolinianus, Senecio densiflorus, Senecio lobatus, Senecio lyratus, Senecio mississipianus Senecio anonymus, Senecio aureus var. angustifolius, Senecio earlei, Senecio smallii
Name authority (Poiret) C. Jeffrey: Kew Bull. 47: 101. (1992) (Alph. Wood) W. A. Weber & Á. Löve: Phytologia 49: 45. (1981)
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