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serpentine groundsel, Siskiyou butterweed, western ragwort

woolly ragwort

Habit Perennials, 7–15+ cm; fibrous-rooted (caudices relatively slender). Perennials, 30–60+ cm; taprooted (caudices relatively thick, weakly ascending or erect), sometimes stoloniferous.
Stems

1, glabrous or sparsely tomentose.

1, densely lanate-tomentose proximally, floccose-tomentose to glabrescent distally.

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.

(and proximal cauline) petiolate;

blades lanceolate to narrowly ovate or elliptic, 40–120+ × 20–50+ mm, bases tapering, sometimes oblique, margins subentire, crenate, or serrate-dentate.

Cauline leaves

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

gradually reduced (± petiolate or sessile, weakly clasping; dentate to pinnately lobed).

Peduncles

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

bracteate, sparsely to densely tomentose.

Ray florets

(8–)13;

corolla laminae 6–10+ mm.

10 or 13;

corolla laminae 6–8+ mm.

Disc florets

35–50+;

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

50–60+;

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

Phyllaries

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

13 or 21, light green, 5–8 mm, usually glabrous (sometimes hairy proximally).

Calyculi

conspicuous (bractlets narrow, red-tinged).

inconspicuous.

Heads

1–4+ in corymbiform arrays.

10–30+ in open, corymbiform arrays (more in robust individuals).

Cypselae

1.5–2 mm, glabrous;

pappi 5–6 mm.

1–1.5 mm, hispid;

pappi 5–7 mm.

2n

= 46.

= 46.

Packera hesperia

Packera tomentosa

Phenology Flowering mid Apr–mid Jun. Flowering (Mar–)May–early Jun.
Habitat Serpentine derived soils, open woodland scrub Open meadows, roadways, sandy or shallow soils overlying granitic outcrops
Elevation 500–2500 m (1600–8200 ft) 0–500 m (0–1600 ft)
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; DE; FL; GA; LA; MD; NC; NJ; OK; SC; TX; VA
[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 tomentosa is common throughout most of its range. The basal and proximal cauline leaves are held at about 45 degrees to the stems.

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

Source FNA vol. 20, p. 589. FNA vol. 20, p. 601.
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. 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. 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. tridenticulata, P. werneriifolia
Synonyms Senecio hesperius, Senecio auleticus Senecio tomentosus, Cineraria integrifolia var. minor, S. alabamensis
Name authority (Greene) W. A. Weber & Á. Löve: Phytologia 49: 47. (1981) (Michaux) C. Jeffrey: Kew Bull. 47: 101. (1992)
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