Centaurea macrocephala

Muss. Puschk. ex Willd.

Sp. Pl., ed. 4 [Willdenow] 3(3): 2298 (-2299). 1803 [Apr-Dec 1803].

Common names: Globe centaurea big-head knapweed yellow bachelor’s button or cornflower centaurée à gros capitules
Introduced
Synonyms: Grossheimia macrocephala (Puschkarew ex Willdenow) Sosnowsky & Takhtajan
Treatment appears in FNA Volume 19. Treatment on page 185. Mentioned on page 183.

Perennials, 50–170 cm. Stems usually several, erect, unbranched or sparingly branched distally, villous with septate hairs, thinly arachnoid-tomentose, fistulose proximal to heads. Leaves short-villous and thinly arachnoid, ± glabrate, resin-gland-dotted; basal and proximal cauline petiolate, blades oblanceolate to narrowly ovate, 10–30 cm, margins entire or shallowly dentate; cauline sessile, shortly decurrent, not much smaller except those crowded proximal to heads, blades lanceolate to ovate, 5–10 cm, entire, often ± undulate, apices acute. Heads disciform or weakly radiant, borne singly, sessile, closely subtended by clusters of reduced leaves. Involucres ovoid to hemispheric, 25–35 mm. Phyllaries: bodies pale green or stramineous, ovate or broadly lanceolate, glabrous, appendages erect to spreading, brown, scarious, abruptly expanded, 1–2 cm wide, ± covering phyllary bodies, lacerate fringed, sometimes tipped by weak spines 1–2 mm, glabrous. Florets many; corollas yellow; corollas of sterile florets slightly expanded, ca. 4 mm; corollas of disc-florets ca. 3.5 mm. Cypselae 7–8 mm; pappi of many setiform scales (“flattened bristles”), 5–8 mm. 2n = 18 (Russia).


Phenology: Flowering summer (Jun–Sep).
Habitat: Garden escape in meadows, grassy clearings
Elevation: 400–2000 m

Distribution

V19-209-distribution-map.gif

Introduced; Ont., Que., Colo., Mich., Wash., Wis., e Europe, w Asia

Discussion

Although Centaurea macrocephala is cultivated as an ornamental and for cut flowers in many areas, it has been declared a noxious weed by the state of Washington because of its potential status as an invader.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."fine" is not a number.

... more about "Centaurea macrocephala"
with fine , 1-celled hairs +  and glabrous +
scarious +
erect;spreading +
fringed +  and lacerate +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
indeterminate +  and determinate +
David J. Keil +  and Jörg Ochsmann +
Muss. Puschk. ex Willd. +
decurrent +
Asteraceae tribe Cynareae +
compound +  and simple +
undulate;lanceolate;ovate +
5 cm50 mm <br />0.05 m <br /> (10 cm100 mm <br />0.1 m <br />) +
stramineous +  and pale green +
10-nerved or 20-nerved +  and rugose +
lanceolate;ovate +
barbed +  and smooth +
Globe centaurea +, big-head knapweed +, yellow bachelor’s button or cornflower +  and centaurée à gros capitules +
actinomorphic +
radial +  and bilateral +
inconspicuous +
expanded +  and slender +
compressed +  and barrel--shaped +
fertile +  and bisexual +
Ont. +, Que. +, Colo. +, Mich. +, Wash. +, Wis. +, e Europe +  and w Asia +
400–2000 m +
glandular-punctate +
puberulent +, strigose +, villous +, tomentose +  and glabrous +
pistillate +, staminate +  and neuter +
4 cm40 mm <br />0.04 m <br /> (?) +
winged +  and beaked +
dispersed +
Garden escape in meadows, grassy clearings +
singly +  and radiant +
indeterminate +
each +  and sessile +
ovoid;hemispheric +
2.5 cm25 mm <br />0.025 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
resin-gland-dotted +, glabrate +, arachnoid +  and short-villous +
reduced +
acute +  and linear-oblong +
dentate +  and entire +
usually lobed +  and dissected +
2-carpellate +
persistent +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Flowering summer (Jun–Sep). +
papillate +  and smooth +
distinct +  and fused +
Sp. Pl., ed. 4 [Willdenow] +
1753 +  and 1754 +
flat;convex +
setiform +
exalbuminous +
Introduced +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
branched +  and unbranched +
fistulose +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
Grossheimia macrocephala +
Centaurea macrocephala +
Centaurea +
species +
tomentose +  and glabrous +
50 cm500 mm <br />0.5 m <br /> (170 cm1,700 mm <br />1.7 m <br />) +
tree +, vine +, shrub +  and subshrub +
15 +, 13 +, 12 +, 11 +, 10 +, 9 +  and 8 +