Sonchus palustris

Linnaeus

Sp. Pl. 2: 793. 1753.

Common names: Marsh sow-thistle
Treatment appears in FNA Volume 19. Treatment on page 275. Mentioned on page 274, 276.

Perennials, 100–150 (–350+) cm. Stem-bases hard, sometimes ± woody. Leaves: blades of mid cauline oblong to lanceolate or linear, 15–20+ × 2–3 (–8+) cm, bases auriculate, auricles lanceolate to linear, ± straight, acute, margins sometimes pinnately lobed, lobes ± deltate to lanceolate or linear (not constricted at bases), terminals usually larger than laterals, entire or dentate (teeth not notably prickly). Peduncles usually setose to stipitate-glandular. Involucres 9–13+ mm. Phyllaries sparsely to densely setose to stipitate-glandular. Corollas: ligules ± equaling tubes. Cypselae stramineous, oblong to ellipsoid, 3.5–4 mm, ribs 4–5 on each face, faces transversely rugulose or tuberculate across and between ribs; pappi 7–9 mm. 2n = 18.


Phenology: Flowering Jul–Sep.
Habitat: Disturbed, marshy sites, wet roadside ditches on peaty sand, railroad ditches, wet fields
Elevation: 0–100 m

Discussion

Sonchus palustris was found in Ontario by D. F. Brunton and C. W. Crompton (1993) in the Ottawa area, and by J. K. Morton and J. M. Venn (1995) in the Waterloo region.

The plants in the flora area are subsp. palustris. Subspecies sosnowskyi (Schchian) Boulos, from a single location in the southern Caucasus of eastern Europe, differs primarily in having glabrous stems, peduncles, and heads.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

... more about "Sonchus palustris"
scarious +
ovate +  and lanceolate +
corymbiform +  and subumbelliform +
indeterminate +  and determinate +
acute;lanceolate to linear +
Philip E. Hyatt +
Linnaeus +
auriculate +
compound +  and simple +
3 cm30 mm <br />0.03 m <br /> (8 cm80 mm <br />0.08 m <br />) +
15 cm150 mm <br />0.15 m <br /> (20 cm200 mm <br />0.2 m <br />) +
oblong;lanceolate or linear +
2cm;3cm +
tuberculate +, rugose +, muricate +  and smooth +
filiform +
barbellulate +  and smooth +
Marsh sow-thistle +
zygomorphic +, actinomorphic +  and (3-)5-merous +
yellow +  and orange +
oblong +  and ellipsoid +
Ont. +  and Europe +
0–100 m +
tuberculate +  and rugulose +
winged +  and beaked +
dispersed +
Disturbed, marshy sites, wet roadside ditches on peaty sand, railroad ditches, wet fields +
indeterminate +
each +  and sessile +
connate +  and coherent +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
campanulate;urceolate +
0.9 cm9 mm <br />0.009 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
less deltate +  and lanceolate or linear +
2-carpellate +
persistent +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
usually setose +  and stipitate-glandular +
Flowering Jul–Sep. +
connate +  and distinct +
setose +  and stipitate-glandular +
27 +  and 50 +
flat;convex +
4 +  and 5 +
exalbuminous +
woody +  and hard +
appendaged +  and truncate +
papillate +
Undefined tribe Lactuceae +
Sonchus palustris +
species +
dentate +  and entire +
usually larger +
taprooted +, stoloniferous +  and rhizomatous +
150 cm1,500 mm <br />1.5 m <br /> (350 cm3,500 mm <br />3.5 m <br />) +
100 cm1,000 mm <br />1 m <br /> (150 cm1,500 mm <br />1.5 m <br />) +
shrub +  and subshrub +