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heath groundsel, wood groundsel, woodland groundsel, woodland ragwort

Elmer's butterweed, Elmer's ragwort

Habit Annuals, (15–)30–80+ cm (taproots fibrous-rooted). Perennials, 10–20(–30) cm (rhizomes trailing or branching).
Herbage

puberulent (hairs abundant, curly).

unevenly villous-tomentose or floccose, glabrescent.

Stems

single.

single (from loosely clustered basal leaves).

Leaves

evenly distributed; petiolate;

blades obovate to oblong, 3–7(–12) × 1–3(–4) cm, usually 1–2-pinnate, bases tapered, ultimate margins dentate (distal leaves similar, clasping, bractlike).

progressively reduced distally; ± petiolate;

blades ovate to oblanceolate, (3–)4–8(–10) × 2–3(–4) cm, bases tapered, margins shallowly dentate (mid and distal leaves smaller, bractlike, often clasping).

Ray florets

0 or 1–8+;

corolla laminae usually 1–2+ mm (barely surpassing phyllaries).

± 8;

corolla laminae 8–15 mm.

Phyllaries

± 13 (± 21), 4–7+ mm, tips greenish or minutely black.

(± 8) ± 13, 8–10 mm, tips black (villous).

Calyculi

0 or of 1–5+ linear to filiform bractlets.

of 2–7 lance-linear to linear bractlets (lengths 1/3–2/3 phyllaries).

Heads

12–24 in corymbiform arrays.

erect or weakly nodding (especially in bud), (2–)5–9(–12) in loose, cymiform arrays.

Cypselae

hairy (especially on angles).

glabrous.

2n

= 40.

= 40.

Senecio sylvaticus

Senecio elmeri

Phenology Flowering late spring–summer (northern areas of cool, climate); winter (southern areas). Flowering summer.
Habitat Mildly disturbed woodlands, open, sandy sites Alpine and subalpine rocky sites and talus slopes
Elevation 100–300 m (300–1000 ft) 2000–3000 m (6600–9800 ft)
Distribution
from FNA
CA; LA; MA; MI; NJ; OH; OR; PA; WA; WI; BC; NB; NF; NS; PE; QC; Eurasia [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
from FNA
WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Senecio sylvaticus is a Eurasian weed that favors cool, wet climates. It is well established in coastal areas of the Pacific Coast and in parts of Newfoundland and Quebec; elsewhere in the flora, it appears to be sporadic.

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

Source FNA vol. 20, p. 563. FNA vol. 20, p. 551.
Parent taxa Asteraceae > tribe Senecioneae > Senecio Asteraceae > tribe Senecioneae > Senecio
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. integerrimus, 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. taraxacoides, S. triangularis, S. viscosus, S. vulgaris, S. warnockii, S. wootonii
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. eremophilus, S. ertterae, S. erucifolius, S. flaccidus, S. fremontii, S. hydrophiloides, S. hydrophilus, S. integerrimus, 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
Synonyms S. crepidineus
Name authority Linnaeus: Sp. Pl. 2: 868. (1753) Piper: Erythea 7: 173. (1899)
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