OregonFlora: Packera streptanthifolia

	Packera streptanthifolia
	cleftleaf groundsel, Rocky Mountain butterweed, Rocky Mountain groundsel
Habit	Plants perennial, 20–50+ cm; caudices weak or stout, horizontal or suberect and fibrous-rooted.
Stems	1 or 2–5, clustered, glabrous or sometimes sparsely pubescent near base and in leaf axils.
Basal leaves	blades oblanceolate to orbiculate; thick; turgid, bases tapering to contracted; margins dentate, dissected; entire, subentire or weakly lobulate; surfaces usually glabrous, sometimes pubescent, petiolate.
Cauline leaves	similar to basal, gradually reduced, petiolate or sessile.
Involucres	campanulate.
Ray florets	8 or 13; rays 5–10 mm.
Disc florets	35–60; corolla tubes 2–4 mm; limbs 2.5–4 mm.
Phyllaries	(8)13 or 21, 4–7+ mm, green; tips sometimes anthocyanic; surfaces glabrous.
Calyculi	conspicuous.
Fruits	1–2.5 mm, glabrous; pappi 3–6 mm.
Heads	2–20+; in corymb- or subumbel-like arrays; peduncles glabrous or sparsely tomentose, bracteate.
2n	=46, 92.

	Packera streptanthifolia
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Forests, open meadows, and valleys in dry to damp loamy soils. Flowering May–Aug. 400–2900 m. BR, BW, ECas, Lava, Owy, Sisk. ID, NV, WA; north to Yukon, northeast to Saskatchewan, east to WY, southeast to NM. Native. Packera streptanthifolia includes weakly defined “phases” that have been treated as distinct species or as varieties. Characteristics used to define those taxa often overlap and are difficult to distinguish; some phases grade into each other.
Source	Flora of Oregon, volume 2, page 324 Debra Trock
Sibling taxa	P. bolanderi, P. cana, P. eurycephala, P. flettii, P. hesperia, P. macounii, P. porteri, P. pseudaurea, P. subnuda
Synonyms	Packera streptanthifolia var. streptanthifolia, Senecio cymbalarioides, Senecio leonardii, Senecio streptanthifolius
Web links	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Packera streptanthifolia

cleftleaf groundsel, Rocky Mountain butterweed, Rocky Mountain groundsel

Habit

Plants perennial, 20–50+ cm; caudices weak or stout, horizontal or suberect and fibrous-rooted.

Stems

1 or 2–5, clustered, glabrous or sometimes sparsely pubescent near base and in leaf axils.

Basal leaves

blades oblanceolate to orbiculate; thick; turgid, bases tapering to contracted;

margins dentate, dissected; entire, subentire or weakly lobulate;

surfaces usually glabrous, sometimes pubescent, petiolate.

Cauline leaves

similar to basal, gradually reduced, petiolate or sessile.

Involucres

campanulate.

Ray florets

8 or 13;

rays 5–10 mm.

Disc florets

35–60;

corolla tubes 2–4 mm;

limbs 2.5–4 mm.

Phyllaries

(8)13 or 21, 4–7+ mm, green;

tips sometimes anthocyanic;

surfaces glabrous.

Calyculi

conspicuous.

Fruits

1–2.5 mm, glabrous;

pappi 3–6 mm.

Heads

2–20+; in corymb- or subumbel-like arrays;

peduncles glabrous or sparsely tomentose, bracteate.

=46, 92.

Packera streptanthifolia

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Forests, open meadows, and valleys in dry to damp loamy soils. Flowering May–Aug. 400–2900 m. BR, BW, ECas, Lava, Owy, Sisk. ID, NV, WA; north to Yukon, northeast to Saskatchewan, east to WY, southeast to NM. Native.

Packera streptanthifolia includes weakly defined “phases” that have been treated as distinct species or as varieties. Characteristics used to define those taxa often overlap and are difficult to distinguish; some phases grade into each other.

Source

Flora of Oregon, volume 2, page 324
Debra Trock

Sibling taxa