Cynara cardunculus subsp. flavescens

Wiklund

Bot. J. Linn. Soc. 109: 120, fig. 15A–D, F–J. 1992.

Treatment appears in FNA Volume 19. Treatment on page 90. Mentioned on page 89.

Leaves armed with spines 1–3 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.


Phenology: Flowering spring–summer (Apr–Jul).
Habitat: Disturbed areas in grasslands, coastal scrub, chaparral, riparian habitats, fallow fields, roadsides
Elevation: 0–500 m

Distribution

V19-42-distribution-map.gif

Introduced; Calif., w Mediterranean region, Macaronesia

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.

Selected References

None.

Lower Taxa

None.

"fine" is not a number.

white-tomentose +
cobwebby-tomentose +
tomentose +  and glabrous +
fringed +  and long-sagittate +
spine-tipped +, spineless +  and tipped +
scarious +
racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
David J. Keil +
Wiklund +
30 cm300 mm <br />0.3 m <br /> (200 cm2,000 mm <br />2 m <br />) +
decurrent +
Asteraceae tribe Cynareae +
compound +  and simple +
with slender to very very stout marginal spines +, spineless +  and compound +
divided +  and lobed +
10-nerved or 20-nerved +  and rugose +
actinomorphic +
purple +  and blue +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
flattened +, 4-angled +, less cylindric +  and obpyramidal +
fertile +  and bisexual +
Calif. +, w Mediterranean region +  and Macaronesia +
0–500 m +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Disturbed areas in grasslands, coastal scrub, chaparral, riparian habitats, fallow fields, roadsides +
in few-headed , terminal , cymiform arrays +  and singly +
indeterminate +
arachnoid-tomentose +
each +  and sessile +
purplish tinged +
5 cm50 mm <br />0.05 m <br /> (15 cm150 mm <br />0.15 m <br />) +
3 cm30 mm <br />0.03 m <br /> (15 cm150 mm <br />0.15 m <br />) +
ovoid;hemispheric +
constricted +
4 cm40 mm <br />0.04 m <br /> (15 cm150 mm <br />0.15 m <br />) +
cauline +  and basal +
oblong +  and lanceolate entire +
innocuous +
truncate +  and entire +
divided +  and lobed +
slender to very +
acute +  and short-acuminate +
lanceolate +  and broadly ovate +
2-carpellate +
2 cm20 mm <br />0.02 m <br /> (4 cm40 mm <br />0.04 m <br />) +
persistent +
Flowering spring–summer (Apr–Jul). +
papillate +  and smooth +
1 cm10 mm <br />0.01 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
distinct +  and fused +
papillate +
Bot. J. Linn. Soc. +
concave;flat or convex +
exalbuminous +
Weedy +, Introduced +  and Illustrated +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
branched +  and simple +
appendaged +  and truncate +
long-exserted +
dilated +  and swollen +
enlarged +
Compositae +
Cynara cardunculus subsp. flavescens +
Cynara cardunculus +
subspecies +
cylindric +
expanded +
innocuous +
slender +
perennial +  and annual +
50 cm500 mm <br />0.5 m <br /> (250 cm2,500 mm <br />2.5 m <br />) +
tree +, vine +, shrub +  and subshrub +