''Onopordum tauricum'', the Taurian thistle or bull cottonthistle, is a species of

thistle Thistle is the common name of a group of flowering plants characterised by leaves with sharp prickles on the margins, mostly in the family Asteraceae. Prickles can also occur all over the planton the stem and on the flat parts of the leaves ...

. It is native to Eurasia and is known in Australia and the western United States as an

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...

. It easily becomes a noxious weed, similar to its relative, '' Onopordum acanthium''. This is a biennial herb producing a sticky, glandular, very spiny stem up to 2 meters tall. The spiny, bright light green leaves are up to 25 centimeters long and are divided into triangular lobes. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

is made up of several large

flower head A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

s each up to 7 centimeters wide. They are lined with long, spiny

phyllaries In botanical terminology, a phyllary, also known an involucral bract or tegule, is a single bract of the involucre of a composite flower. The involucre is the grouping of bracts together. Phyllaries are reduced leaf-like structures that form one o ...

and bear pink-purple tubular flowers up to 3 centimeters long.

References

External links

Jepson Manual TreatmentOregon Noxious Weeds
* tauricum Flora of France Flora of Germany Flora of Southeastern Europe Flora of Ukraine Flora of the Crimean Peninsula Flora of the North Caucasus Flora of Western Asia Plants described in 1803 {{Cynareae-stub