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heath groundsel, wood groundsel, woodland groundsel, woodland ragwort

oxford ragwort

Habit Annuals, (15–)30–80+ cm (taproots fibrous-rooted). Annuals (or perennials), 15–60+ cm (taprooted).
Herbage

puberulent (hairs abundant, curly).

sparsely, unevenly floccose to subglabrous, glabrescent.

Stems

single.

single (branching distally).

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).

evenly distributed;

petiolate (proximal, petioles ± winged);

blades obovate to oblong, 4–10 × 2–4+ cm, mostly lyrate-pinnatifid to pinnate, bases tapered, ultimate margins dentate (distal leaves similar, smaller, sessile).

Ray florets

0 or 1–8+;

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

± 13;

corolla laminae 5–8 mm.

Phyllaries

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

(± 13) ± 21, 5–6+ mm, tips black.

Calyculi

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

of 4–10+ bractlets (1–2+ mm).

Heads

12–24 in corymbiform arrays.

(3–)6–20 in open, cymiform arrays.

Cypselae

hairy (especially on angles).

usually hairy.

2n

= 40.

= 20.

Senecio sylvaticus

Senecio squalidus

Phenology Flowering late spring–summer (northern areas of cool, climate); winter (southern areas). Flowering late winter–spring or fall.
Habitat Mildly disturbed woodlands, open, sandy sites Disturbed sites (in regions of cool, damp climates)
Elevation 100–300 m [300–1000 ft] 0–300 m [0–1000 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
CA; NS; Europe [Introduced in North America]
[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.)

Senecio squalidus is native in Europe, where it is a common weed. It is apparently established in the San Francisco Bay area, California and has been reported from British Columbia, New Brunswick, and Nova Scotia. It is to be expected elsewhere.

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

Source FNA vol. 20, p. 563. Treatment author: Theodore M. Barkley†. FNA vol. 20, p. 560. Treatment author: Theodore M. Barkley†.
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. 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. sylvaticus, S. taraxacoides, S. triangularis, S. viscosus, S. vulgaris, S. warnockii, S. wootonii
Name authority Linnaeus: Sp. Pl. 2: 868. (1753) Linnaeus: Sp. Pl. 2: 869. (1753)
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