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serpentine groundsel, Siskiyou butterweed, western ragwort

Brewer's ragwort

Habit Perennials, 7–15+ cm; fibrous-rooted (caudices relatively slender). Perennials or biennials, 40–100+ cm; fibrous-rooted (caudices erect, stout).
Stems

1, glabrous or sparsely tomentose.

1, glabrous or leaf axils 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.

(and proximal cauline) petiolate;

blades spatulate to obovate (pinnately lobed, terminal lobes ovate to oblong, lateral lobes 2–6+ pairs, smaller, midribs narrowly winged), 100–300+ × 20–50(–80+) mm, bases contracted to tapering, ultimate margins crenate or dentate to lacerate (faces glabrous).

Cauline leaves

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

gradually reduced (petiolate or sessile; obovate, irregularly incised to subpinnate, terminal lobes narrow).

Peduncles

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

usually ebracteate (rarely with 1–2 bractlets), glabrous.

Ray florets

(8–)13;

corolla laminae 6–10+ mm.

8–10+;

corolla laminae 10–15+ mm.

Disc florets

35–50+;

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

45–60+;

corolla tubes 3–3.5 mm, limbs 4–4.5 mm.

Phyllaries

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

13 or 21, green, 7–9+ mm, glabrous.

Calyculi

conspicuous (bractlets narrow, red-tinged).

inconspicuous.

Heads

1–4+ in corymbiform arrays.

15–50+ in corymbiform arrays.

Cypselae

1.5–2 mm, glabrous;

pappi 5–6 mm.

2–2.5 mm, glabrous;

pappi 6–7 mm.

2n

= 46.

= 46.

Packera hesperia

Packera breweri

Phenology Flowering mid Apr–mid Jun. Flowering mid Apr–late May.
Habitat Serpentine derived soils, open woodland scrub Dry, rocky soils, partially shaded or protected areas, grasslands, oak savannas, roadsides, disturbed areas
Elevation 500–2500 m (1600–8200 ft) 200–1500 m (700–4900 ft)
Distribution
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[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 breweri is known only from Coast Ranges from San Francisco Bay to Los Angeles County and along the eastern edges of the San Joaquin Valley. Populations are relatively small and sporadic; the plants appear not to hybridize with other species of Packera.

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

Source FNA vol. 20, p. 589. FNA vol. 20, p. 580.
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. 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 breweri
Name authority (Greene) W. A. Weber & Á. Löve: Phytologia 49: 47. (1981) (Burtt Davy) W. A. Weber & Á. Löve: Phytologia 49: 46. (1981)
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