Information on Slender Thistle

Common Name: Slender Thistle
Scientific Name: Carduus tenuiflorus
Irish Name: Feochadán caol
Family Group: Asteraceae
Distribution: View Map (Courtesy of the BSBI)
Flowering Period


Click for list of all flowering by month
Slender Thistle could sometimes be confused with:

Thistle, Marsh, Thistle, Creeping,

This rather slender thistle, which can grow to more than 1m high, is a very spiny plant. Annual or biennial, it has spiny wings running up the stems to its clusters of small, pinkish-red congested, unstalked flower-heads (8mm across) which are cottony, with bracts which have a curved spine at their tops.They bloom from June to August and have lobed leaves which are very spiny and are cottony below.  This plant is found on open ground and grassy places, more commonly in coastal areas.  It is a native plant and belongs to the family Asteraceae.

My first record of this plant was in 2008 near Tacumshane, Co Wexford when I also photographed it.   

If you are satisfied you have correctly identified this plant, please submit your sighting to the National Biodiversity Data Centre

Thistle, Slender
Thistle, Slender

This species is classed as NEAR THREATENED in the Red Data List of Vascular Plants 2016.