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lambstongue ragwort, western groundsel

ballhead ragwort, mountain marsh butterweed

Habit Herbs perennial or biennial, (1)2–7 dm; caudices button-like, with fleshy, fibrous, unbranched roots. Herbs perennial, (3)4–8 dm; caudices ± woody, branching, with stout rhizomes.
Stems

1, loosely arachnoid-tomentose, or villous, glabrate with age.

1, tomentose or unevenly glabrate.

Leaves

mostly basal;

cauline progressively reduced distally; ± petiolate;

basal and lower cauline elliptic, lanceolate, linear, oblanceolate, rounded-deltate, rarely suborbiculate, bases tapered or truncate to cordate;

margins entire or dentate;

distal becoming sessile and bract-like.

mostly basal;

basal present at flowering;

cauline reduced distally;

distal much reduced and bract-like, oblanceolate to elliptic, bases tapered;

margins weakly dentate or denticulate with callous denticles;

surfaces sparsely tomentose to nearly glabrous, petiolate.

Inflorescences

corymb-like arrays;

bracts 0 or inconspicuous.

corymb-like arrays;

bracts conspicuous.

Involucres

urn-shaped.

campanulate.

Ray florets

5, rarely 0;

rays 6–15(20) mm, yellow or white to pale yellow.

~13;

rays 6–10 mm.

Disc florets

35–45.

25–35+.

Phyllaries

(8)13 or 21;

tips usually black, sometimes green.

(13)21, 3–7 mm;

tips black or dark brown.

Calyculi

1–5+, inconspicuous, usually < 2 mm.

1–5 bractlets, 2–3 mm.

Fruits

2.5–3 mm, usually glabrous, sometimes hairy along ribs.

1.5–2.5 mm, usually hairy, sometimes glabrous.

Heads

6–15(30+).

(3)5–24, usually > 10.

2n

=40, 80.

=40.

Senecio integerrimus

Senecio sphaerocephalus

Distribution
[WildflowerSearch map]
[BONAP county map]
[WildflowerSearch map]
[BONAP county map]
Discussion

Western North America. 5 varieties; 3 varieties treated in Flora.

Open meadows, near conifer forests. Flowering Jun–Jul. 1100–1700 m. BW. ID, NV; northeast to MT, east to WY, southeast to CO. Native.

Although Senecio sphaerocephalus has been collected in Oregon, it is relatively rare within the state and more abundant in the more easterly parts of its range.

Source Flora of Oregon, volume 2, page 339
Debra Trock
Flora of Oregon, volume 2, page 340
Debra Trock
Sibling taxa
S. aronicoides, S. crassulus, S. ertterae, S. fremontii, S. hydrophiloides, S. hydrophilus, S. jacobaea, S. serra, S. sphaerocephalus, S. sylvaticus, S. triangularis, S. viscosus, S. vulgaris
S. aronicoides, S. crassulus, S. ertterae, S. fremontii, S. hydrophiloides, S. hydrophilus, S. integerrimus, S. jacobaea, S. serra, S. sylvaticus, S. triangularis, S. viscosus, S. vulgaris
Subordinate taxa
S. integerrimus var. exaltatus, S. integerrimus var. major, S. integerrimus var. ochroleucus
Web links