OregonFlora: Silybum marianum

	Silybum marianum
	milk thistle
Habit	Plants 1.5–30 dm.
Leaves	6–50+ cm, with 1 main vein.
Involucres	3–6 cm including spinetips.
Florets	25–100+; corollas 25–35 mm, exserted from involucres, pink to purple.
Fruits	6–8 mm, brown to purple, mottled; surfaces glabrous; pappi 15–20 mm.
2n	=18.

	Silybum marianum
Distribution	[WildflowerSearch map] [BONAP county map]
Discussion	Roadsides, riverbanks, fields, disturbed areas. Flowering Apr–Sep. 0–300 m. CR, Est, Sisk, WV. CA, NV, WA; widely scattered in North America; Mediterranean. Exotic.
Source	Flora of Oregon, volume 2, page 343 Kenton Chambers
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Silybum marianum

milk thistle

Habit

Plants 1.5–30 dm.

Leaves

6–50+ cm, with 1 main vein.

Involucres

3–6 cm including spinetips.

Florets

25–100+;

corollas 25–35 mm, exserted from involucres, pink to purple.

Fruits

6–8 mm, brown to purple, mottled;

surfaces glabrous;

pappi 15–20 mm.

=18.

Silybum marianum

Distribution

[WildflowerSearch map]

[BONAP county map]

Discussion

Roadsides, riverbanks, fields, disturbed areas. Flowering Apr–Sep. 0–300 m. CR, Est, Sisk, WV. CA, NV, WA; widely scattered in North America; Mediterranean. Exotic.

Source

Flora of Oregon, volume 2, page 343
Kenton Chambers

Web links