26-7-2024 DUNMORE EAST, IRELAND - PERENNIAL SOW THISTLE (Sonchus arvensis)

Sonchus arvensis, the field milk thistle, field sowthistle, perennial sow-thistle, corn sow thistle, dindle, gutweed, swine thistle, or tree sow thistle, is a species of flowering plant in the family Asteraceae. S. arvensis often occurs in annual crop fields and may cause substantial yield losses.

The plant grows up to 1.5 metres (4 ft 11 in) in height,: 744  with leaves 10–35 cm (4–13+3⁄4 in) long and 4–14 cm (1+1⁄2–5+1⁄2 in) wide.[7] It produces conspicuous yellow flowerheads about 3–5 cm (1+1⁄4–2 in) wide, which are visited by various types of insects—especially hoverflies of the genus Eristalis.

Sonchus arvensis is native to Eurasia, where it is widespread across most of the continent. It has also become naturalized in many other regions, and is considered an invasive noxious weed in some places, such as North America (including Prince Edward Island), Russia, New Zealand, and Australia.

It grows in areas such as pastures, roadsides, bushlands and the shorelines of lakes, rivers and sea coast.

A study conducted in 2003 has shown that with future global atmospheric carbon levels, S. arvensis shows increased growth with increased atmospheric carbon which could potentially expand its range and outcompete native species.