The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

serpentine groundsel, Siskiyou butterweed, western ragwort

Small's ragwort

Habit Perennials, 7–15+ cm; fibrous-rooted (caudices relatively slender). Perennials, 30–70+ cm; fibrous-rooted (caudices erect to ascending).
Stems

1, glabrous or sparsely tomentose.

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

Basal leaves

(and proximal cauline) petiolate;

blades ovate, oblanceolate, or spatulate, 10–30 × 5–20 mm, bases tapering, sometimes obtuse, margins entire, subentire, or dentate.

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

abruptly reduced (sessile, clasping; bractlike, entire).

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

Peduncles

bracteate (bractlets red-tinged), densely lanate-tomentose.

bracteate, distally tomentose.

Ray florets

(8–)13;

corolla laminae 6–10+ mm.

8 or 13;

corolla laminae 5–7+ mm.

Disc florets

35–50+;

corolla tubes 2.5–3.5 mm, limbs 3–4 mm.

45–60+;

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

Phyllaries

(13–)21, green (tips red or dark red), densely tomentose proximally.

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

Calyculi

conspicuous (bractlets narrow, red-tinged).

inconspicuous.

Heads

1–4+ in corymbiform arrays.

20–70(–100+) in corymbiform arrays.

Cypselae

1.5–2 mm, glabrous;

pappi 5–6 mm.

0.75–1 mm, hirsute on ribs;

pappi 2.5–3 mm.

2n

= 46.

= 44.

Packera hesperia

Packera anonyma

Phenology Flowering mid Apr–mid Jun. Flowering early Jun–mid Jul (north), early Apr–late May (south).
Habitat Serpentine derived soils, open woodland scrub Open fields, meadows, roadsides, disturbed sites, in drying or sandy soils
Elevation 500–2500 m (1600–8200 ft) 50–1800 m (200–5900 ft)
Distribution
from FNA
CA; OR
[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

Of conservation concern.

Packera hesperia is known only from the Siskiyou Mountains.

(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. 589. 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. glabella, P. greenei, P. hartiana, 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 hesperius, Senecio auleticus Senecio anonymus, Senecio aureus var. angustifolius, Senecio earlei, Senecio smallii
Name authority (Greene) W. A. Weber & Á. Löve: Phytologia 49: 47. (1981) (Alph. Wood) W. A. Weber & Á. Löve: Phytologia 49: 45. (1981)
Web links