Flora of North America species comparison

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

Cynara cardunculus subsp. flavescens

Cynara cardunculus
Photo is of parent taxon

cardoon

artichoke, artichoke thistle, cardoon
Taproots

fleshy.
Stems

glabrous to densely arachnoid-tomentose.
Leaves

armed with spines 1–3 cm.

basal blades 30–200 cm, margins deeply 1–2-pinnately lobed or divided to nearly compound, lobes oblong to lanceolate, entire to coarsely toothed, teeth and lobes innocuous to prominently spine-tipped, spines 1–30 mm, often clustered along petiole and at base of lobes, abaxial faces densely gray- or white-tomentose, adaxial faces thinly cobwebby-tomentose;

cauline leaves often short-decurrent as spiny wings.
Involucres

often purplish tinged, 30–150 × 40–150 mm excluding spreading phyllary tips, constricted distally or not.
Corollas

blue or purple (rarely white), 3–5 cm;

styles long-exserted.
Phyllaries

lanceolate to broadly ovate, bases appressed, spreading apices obtuse to acute or acuminate, spineless or tipped with spines 1–9 mm or truncate, abruptly mucronate, and spineless or minutely spine-tipped.
Cypselae

4–8 mm;

pappus bristles 2–4 cm.
Middle

phyllaries acute to short-acuminate at apex with point 10–21 mm and spine tip 2–5(–6) mm, distal margins with prominent yellowish margins 0.5–1+ mm.

Cynara cardunculus subsp. flavescens

Cynara cardunculus
Phenology Flowering spring–summer (Apr–Jul).
Habitat Disturbed areas in grasslands, coastal scrub, chaparral, riparian habitats, fallow fields, roadsides
Elevation 0–500 m (0–1600 ft)
Distribution
from FNA
CA; w Mediterranean region; Macaronesia [Introduced in North America]
[BONAP county map]
from FNA
CA; Mediterranean region; Macaronesia [Introduced in North America]
[WildflowerSearch map]
[BONAP county map]
Discussion

Artichoke thistle is a noxious weed that tends to spread aggressively in overgrazed range lands and may invade undisturbed natural vegetation as well. Dense infestations form pure stands, sometimes several hec-tares in extent. The long, needlelike spines deter herbivores and the large rosettes suppress the growth of other plants. Vigorous root sprouts can develop from fragments of the deep taproots left in the soil by cultivation or mechanical clearing.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Subspecies 2 (2 in the flora).

Cynara cardunculus is a species of considerable economic importance. The globe artichoke, formerly treated as C. scolymus, was included as a horticulturally derived form of C. cardunculus (A. Wiklund 1992). The artichoke and the cardoon, another horticultural race of C. cardunculus, have been cultivated for centuries–the former for edible phyllary bases and receptacles, and the latter for edible stems and leaf rachises. That species has a darker side, however. Wild type races (artichoke thistles) are invasive and tenacious weeds that have infested Mediterranean climate areas of California, South America, South Africa, and Australia. Wiklund recognized two subspecies of C. cardunculus: subsp. cardunculus includes the artichoke, cardoon, and various wild types; subsp. flavescens includes some of the most invasive weedy members of the species. It is not certain that all of the weedy artichoke thistles in California are members of the latter subspecies.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Key
1. Middle involucral bracts broadly obtuse, truncate or emarginate to long-acuminate, apices with or without very narrow yellowish margins, spineless or tipped with slender spines to 9 mm
subsp. cardunculus
1. Middle involucral bracts acute to short-acuminate, apices with yellowish margins 0.5–1 mm wide, tipped with stout spines to 2–5 mm
subsp. flavescens
Source FNA vol. 19, p. 90. FNA vol. 19, p. 89.
Parent taxa Asteraceae > tribe Cardueae > Cynara > Cynara cardunculus Asteraceae > tribe Cardueae > Cynara
Sibling taxa
C. cardunculus subsp. cardunculus
Subordinate taxa
C. cardunculus subsp. cardunculus, C. cardunculus subsp. flavescens
Name authority Wiklund: Bot. J. Linn. Soc. 109: 120, fig. 15A–D, F–J. (1992) Linnaeus: Sp. Pl. 2: 827. (1753)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers