The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

lambstongue ragwort, mountain butterweed, one-stem butterweed, tall western groundsel, western groundsel

Photo is of parent taxon

big-head groundsel, lambs-tongue ragwort, lambstongue groundsel

Habit Perennials (possibly biennials), (10–)20–70 cm (caudices buttonlike, roots fleshy-fibrous).
Herbage

arachnose, loosely tomentose, or villous (hairs crisped, jointed), glabrescent.

usually copiously arachnose, tomentose, or villous at flowering.

Stems

single.

Leaves

progressively reduced distally; ± petiolate;

blades elliptic, lanceolate, linear, oblanceolate, rounded-deltate, or suborbiculate, 6–25 × 1–6 cm, bases ± tapered or truncate to cordate, margins entire or ± dentate (distal leaves sessile, bractlike).

basal and proximal cauline distinctly petiolate;

blades (cauline) usually lanceolate to oblanceolate.

Ray florets

usually ± 8 or ± 13, sometimes 0;

corolla laminae 6–15(–20) mm (usually yellow, ochroleucous to white in one variety).

usually 5;

corollas yellow, laminae mostly 5–8 mm.

Phyllaries

usually ± 13 or ± 21, rarely ± 8, (4–)5–12(–15) mm, tips usually black, sometimes green.

linear-subulate, 8–12 mm, tips usually green, minutely, if at all, black.

Calyculi

of 1–5+ linear to filiform bractlets (seldom more than 2 mm).

Heads

6–20(–40+) in corymbiform arrays (peduncle of terminal head often shorter than others).

6–12(–30+).

Cypselae

usually glabrous, sometimes hirtellous (mostly on angles).

2n

= 40, 80.

Senecio integerrimus

Senecio integerrimus var. major

Phenology Flowering spring.
Habitat Openings in coniferous woodlands and woodland-sagebrush associations
Elevation 100–3600 m (300–11800 ft)
Distribution
from FNA
CA; CO; IA; ID; KS; MN; MT; ND; NE; NM; NV; OR; SD; UT; WA; WY; AB; BC; MB; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV; OR
[BONAP county map]
Discussion

Varieties 5 (5 in the flora).

The varieties of Senecio integerrimus are distinguished by morphology and geography.

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

Variety major is most frequent in the Sierra Nevada, especially on the western slope; eastward, it passes into var. exaltatus.

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

Key
1. Basal leaves with distinct petioles, blades usually ovate to rounded-deltate, sometimes obovate to oblanceolate; ray corollas white or ochroleucous
var. ochroleucus
1. Basal leaves with or without distinct petioles, blades elliptic, lanceolate, oblanceolate, rounded-deltate, sublinear, or suborbiculate; ray corollas yellow (or rays 0)
→ 2
2. Herbage glabrous or glabrate at flowering (except in leaf axils and among heads); phyllaries linear-subulate, tips usually green, minutely (if at all) black
var. integerrimus
2. Herbage usually arachnose, tomentose, or villous at flowering; phyllaries lanceolate to linear-subulate, tips black (if minutely so, then narrowly lanceolate and broader than subulate)
→ 3
3. Basal and proximal leaves oblong or lanceolate to sublinear; heads 3–6(–16+); phyllaries 10–15+ mm
var. scribneri
3. Basal and proximal leaves mostly elliptic to oblanceolate, sometimes elliptic or rounded-deltate to suborbiculate; heads usually 6–15(–30+; if fewer than 6, leaves lanceolate or broader); phyllaries 5–12 mm.
→ 4
4. Plants copiously arachnose, tomentose, or villous at flowering; phyllaries linear-subulate, 8–12 mm, tips minutely, if at all, blackened
var. major
4. Plants copiously to sparsely arachnose, tomentose, or villous at flowering; phyllaries mostly lanceolate (seldom as narrow as linear-subulate), 5–10 mm, tips black
var. exaltatus
Source FNA vol. 20, p. 556. FNA vol. 20, p. 557.
Parent taxa Asteraceae > tribe Senecioneae > Senecio Asteraceae > tribe Senecioneae > Senecio > Senecio integerrimus
Sibling taxa
S. actinella, S. amplectens, S. ampullaceus, S. aphanactis, S. arizonicus, S. aronicoides, S. astephanus, S. atratus, S. bigelovii, S. blochmaniae, S. californicus, S. cannabifolius, S. clarkianus, S. crassulus, S. elegans, S. elmeri, S. eremophilus, S. ertterae, S. erucifolius, S. flaccidus, S. fremontii, S. hydrophiloides, S. hydrophilus, S. jacobaea, S. lemmonii, S. lugens, S. lyonii, S. megacephalus, S. mohavensis, S. multidentatus, S. neowebsteri, S. parryi, S. pattersonensis, S. pseudoarnica, S. pudicus, S. quaylei, S. rapifolius, S. riddellii, S. sacramentanus, S. scorzonella, S. serra, S. sheldonensis, S. soldanella, S. spartioides, S. sphaerocephalus, S. spribillei, S. squalidus, S. sylvaticus, S. taraxacoides, S. triangularis, S. viscosus, S. vulgaris, S. warnockii, S. wootonii
S. integerrimus var. exaltatus, S. integerrimus var. integerrimus, S. integerrimus var. ochroleucus, S. integerrimus var. scribneri
Subordinate taxa
S. integerrimus var. exaltatus, S. integerrimus var. integerrimus, S. integerrimus var. major, S. integerrimus var. ochroleucus, S. integerrimus var. scribneri
Synonyms S. eurycephalus var. major, S. lugens var. megacephalus, S. mendocinensis, S. whippleanus
Name authority Nuttall: Gen. N. Amer. Pl. 2: 165. (1818) (A. Gray) Cronquist: Aliso 4: 100. (1958)
Web links