Vascular Plants of North Carolina
Account for Yellow Thistle - Cirsium horridulum   Michaux
Members of Asteraceae:
Members of Cirsium with account distribution info or public map:
Google Images
Section 6 » Order Asterales » Family Asteraceae
DistributionFrom the outer Coastal Plain to the western Piedmont; scattered in the low Mountains. The large gap in the northwestern Coastal Plain and northeastern Piedmont is probably due to a lack of collecting.

Southern ME, to FL and TX. Mostly Coastal Plain and Piedmont but scattered farther inland.
AbundanceCommon in the eastern half of the Coastal Plain, and west through the Sandhills region. Fairly common to common in the eastern 2/3 of the Piedmont. Rare in the Mountains and foothills. Scarcity of records in the northwestern Coastal Plain and northeastern Piedmont is puzzling; certainly uncommon there.
HabitatDry sandy soils of pine-oak woodlands, openings in woodlands, pine savannas, roadsides, powerlines, and rocky open slopes. Mostly in disturbed habitats.
PhenologyFlowers and fruits late March - early June.
IdentificationUniquely among our thistles, this species has long, broad, leaflike inflorsecence bracts, and which are armed with long yellowish spines. Leaves and stems are also densely spiny, making this a no-go zone! Plants come in two flower morphs, dull yellow or red-maroon. This is the most often seen thistle in the Piedmont, a familiar species in most areas there.
Taxonomic CommentsRAB (1968) named this species as Carduus spinosissimus. Weakley (2018) lists two varieties in NC -- var. horridulum and the rather rare var. vittatum. The former C. smallii has been included within C. horridulum, as C. horridulum var. vittatum.

Other Common Name(s)Bristle Thistle, Horrid Thistle, Bull Thistle (the usual common name of the exotic C. vulgare)
State RankS5
Global RankG5
State Status
US Status
USACE-agcpFAC link
USACE-empFACU link
County Map - click on a county to view source of record.
Photo Gallery
B.A. SorrieRoadside, Stanly County, May 2009. StanlyPhoto_natural
B.A. Sorriesame data OnslowPhoto_natural
B.A. SorrieOnslow County, Sandy Run Natural Area, roadsides. 7 June 2022. OnslowPhoto_natural

View Mapping Selection Options
Select a source
Select an occurrence type