The genus is named after the Ancient Greek for such plants.
 All are characterized by soft, somewhat irregularly lobed leaves that clasp the stem and, at least initially, form a basal rosette.
 The stem contains a milky latex.
 Flower heads are yellow and range in size from half to one inch in diameter; the florets are all of ray type.
Sonchus fruits are single-seeded, dry and indehiscent.
Sow thistles are common roadside plants, and while native to Eurasia and tropical Africa, they are found almost worldwide in temperate regions.

Mature sow thistle stems can range from 30 cm to 2 m (1 to 6 ft) tall, depending upon species and growing conditions.
 Coloration ranges from green to purple in older plants.
 Sow thistles exude a milky latex when any part of the plant is cut or damaged, and it is from this fact that the plants obtained the common name, "sow thistle", as they were fed to lactating sows in the belief that milk production would increase.
Sow thistles are known as "milk thistles" in some regions, although true milk thistles belong to the genus Silybum.
The genus is named after the Ancient Greek for such plants.  All are characterized by soft, somewhat irregularly lobed leaves that clasp the stem and, at least initially, form a basal rosette.  The stem contains a milky latex.  Flower heads are yellow and range in size from half to one inch in diameter; the florets are all of ray type. Sonchus fruits are single-seeded, dry and indehiscent. Sow thistles are common roadside plants, and while native to Eurasia and tropical Africa, they are found almost worldwide in temperate regions.
Mature sow thistle stems can range from 30 cm to 2 m (1 to 6 ft) tall, depending upon species and growing conditions.  Coloration ranges from green to purple in older plants.  Sow thistles exude a milky latex when any part of the plant is cut or damaged, and it is from this fact that the plants obtained the common name, "sow thistle", as they were fed to lactating sows in the belief that milk production would increase. Sow thistles are known as "milk thistles" in some regions, although true milk thistles belong to the genus Silybum.
Sonchus