Sonchus asper (L.) Hill

Remark The words or terms in red (actually dark orange) in the text are defined in a glossary.

july_16_10.gthmb can't be loaded. Sonchus asper is an introduced plant native to Eurasia. It is an annual, growing 0.4 to 1.5 m tall. Its stems branch near the top. Its leaves, which have weak marginal prickles, clasp the stem. Plants contain a bitter milky juice. Flowers are golden-yellow, up to 25 mm (1 inch) broad. It is spread entirely by seed.

The plant belongs to the Asteraceae family.


Many sources, copied from one another ? say that the genus name is from the Greek sonchos, the plant's initial name, and means hollow in reference to the stems. I checked in my Dictionnaire Grec Français by Anatole Bailly, also called Le Grand Bailly, one of the quite renowned dictionary of classical Greek, and I could not find one entry starting in σον (son) or σων (sôn), so...

In Latin, asper means rough, harsh, rugged and refers to the prickles on the leaves margins.

Common names

Some of the vernacular names of Sonchus asper are: Sowthistle, Prickly Sowthistle, Spiny-leaf Sow-thistle, Spiny-leaved Sow Thistle and Spiny Sowthistle. Some of the French common names are: Chaudronnet, Laiteron épineux, Laiteron rude, Laiteron maraîcher.


Pyrola chlorantha has also been known as:


draw.jpg can't be loaded. Sonchus asper can be identified by its prickly curled leaves, clasping the stem at their base, and its yellow ligulate flower heads arranged in a small panicle at the top of the plant.

Sonchus asper differs from other Sonchus species by its flowering heads less than 1 inch in diameter and by its wrinkled achenes.

Sonchus oleraceus looks quite similar to Sonchus asper. The difference in the two plants lies in that Sonchus oleraceus has leaf auricles which come to an acute point, those of Sonchus asper are always rounded. The lower leaves of Sonchus oleraceus are nearly always deeply lyrate-pinnatifid. Sonchus oleraceus is a much less stout species also which can be handled easily without injury to the person doing the handling. The prickly leaves and big taproot make Sonchus asper difficult at best to remove from the ground.


Sonchus asper is a prolific annual that has ovate, shiny cotyledons




Flower heads



Sonchus asper is a common weed and most frequently occurs on roadsides, cultivated, waste and fallow ground, field margins, meadows, ditches, disturbed sites, gardens and neglected areas. It often appears in pastures and crops; it rarely causes significant problems, as it is readily grazed in pasture and out-competed by most crops.


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Sonchus asper is found in all of North America except northern Canada. It is also found in Europe, including Britain, in North Africa, in northern and western Asia. The maps shows the plant distribution.


The tender young leaves and stem tops can be eaten, raw or cooked, they can be added to salads or used like spinach. The young leaves are said to have a mild agreeable flavour. The stems should be bruised and the bitter-tasting milky juice washed out before eating or cooking.


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Flower heads

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