The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

compact-headed thistle, Italian thistle

compact-headed thistle, Italian thistle

Habit Plants annual, 2–20 dm. Plants annual, 2–20 dm.
Basal leaves

10–25 cm, deeply lobed or pinnatifid.

10–25 cm, deeply lobed or pinnatifid.

Cauline leaves

obovate or oblanceolate to linear-elliptic, 4–15 cm, shallowly or deeply lobed or pinnatifid;

lobe margins and tips spiny;

surfaces abaxially tomentose, adaxially hispid-pustulose.

obovate or oblanceolate to linear-elliptic, 4–15 cm, shallowly or deeply lobed or pinnatifid;

lobe margins and tips spiny;

surfaces abaxially tomentose, adaxially hispid-pustulose.

Involucres

cylindric or ellipsoid, 10–25 mm in diameter.

cylindric or ellipsoid, 10–25 mm in diameter.

Disc florets

corollas 14–16 mm, purple.

corollas 14–16 mm, purple.

Phyllaries

narrowly lanceolate;

margins not membranous; midribs prominent.

narrowly lanceolate;

margins not membranous; midribs prominent.

Fruits

4–6 mm, tan or brown;

pappus bristles 15–20 mm.

4–6 mm, tan or brown;

pappus bristles 15–20 mm.

Heads

2–5 per cluster;

peduncles winged.

2–5 per cluster;

peduncles winged.

2n

=54, 60, 62.

=54, 60, 62.

Carduus pycnocephalus

Carduus pycnocephalus

Distribution
[WildflowerSearch map]
[BONAP county map]
Discussion

Disturbed areas, waste areas, riverbanks. Flowering May–Jul. 50–700 m. CR, Sisk, WV. CA, ID; widely scattered in US; Asia, Europe. Exotic.

Disturbed areas, waste areas, riverbanks. Flowering May–Jul. 50–700 m. CR, Sisk, WV. CA, ID; widely scattered in US; Asia, Europe. Exotic.

Source Flora of Oregon, volume 2, page 211
Kenton Chambers
Flora of Oregon, volume 2, page 211
Kenton Chambers
Sibling taxa
C. acanthoides, C. crispus, C. nutans, C. tenuiflorus
C. acanthoides, C. crispus, C. nutans, C. pycnocephalus, C. tenuiflorus
Synonyms Carduus pycnocephalus ssp. pycnocephalus Carduus pycnocephalus ssp. pycnocephalus
Web links