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

Habit Perennials, 7–15+ cm; fibrous-rooted (caudices relatively slender).
Stems

1, glabrous or sparsely 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.

Cauline leaves

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

Peduncles

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

Ray florets

(8–)13;

corolla laminae 6–10+ mm.

Disc florets

35–50+;

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

Phyllaries

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

Calyculi

conspicuous (bractlets narrow, red-tinged).

Heads

1–4+ in corymbiform arrays.

Cypselae

1.5–2 mm, glabrous;

pappi 5–6 mm.

2n

= 46.

Packera hesperia

Phenology Flowering mid Apr–mid Jun.
Habitat Serpentine derived soils, open woodland scrub
Elevation 500–2500 m (1600–8200 ft)
Distribution
from FNA
CA; OR
[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.)

Source FNA vol. 20, p. 589.
Parent taxa 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
Synonyms Senecio hesperius, Senecio auleticus
Name authority (Greene) W. A. Weber & Á. Löve: Phytologia 49: 47. (1981)
Web links