Tragopogon dubius, commonly known as yellow salsify, is a species of salsify with yellow flower heads. It is native to Eurasia and has been introduced to North America.
Like most salsifies, Tragopogon dubius grows as an annual or occasionally biennial forb,[citation needed] reaching a height of 40–80 centimetres (15+1⁄2–31+1⁄2 in). The leaves are up to 25 cm (10 in) long.
The buds are blue-green, tall, and tapered. On display from late spring to late summer, the yellow flower head is 4–5 cm (1+1⁄2–2 in) wide.[2] The inflorescence opens early in the morning and often closes up by late afternoon. Later, the plant forms a seed head resembling that of dandelions, but distinctly larger.
The seeds (known as achenes) are 2–4 cm long but featherweight, weighing about 8 mg each on average. There is some natural variation between the central and peripheral achenes in the seedhead, with the peripheral ones being generally darker and heavier, and having a higher concentration of phenolic compounds; this may enhance their survival potential.
