Cirsium cymosum

(Greene) J. T. Howell

Amer. Midl. Naturalist 30: 37. 1943.

Endemic
Basionym: Carduus cymosus Greene Fl. Francisc., 480. 1897
Synonyms: Cirsium botrys Petrak Cirsium triacanthum Petrak
Treatment appears in FNA Volume 19. Treatment on page 136. Mentioned on page 105, 108.

Biennials or perennials, 25–120 cm, pubescence a mixture of fine, non-septate arachnoid trichomes and coarser, septate trichomes, especially along stems and on midveins on abaxial leaf faces, usually ± loose and irregularly deciduous from leaves in age; taprooted. Stems usually 1, erect, ± gray-tomentose, sometimes villous with septate trichomes; branches 0–10+, usually arising in distal 1/2, ascending, usually reaching a ± common height. Leaves: blades linear-oblong to oblanceolate or elliptic, 10–30 × 3–7 cm, shallowly to deeply pinnatifid with 3–8 pairs of lobes, longer than 2 cm, lobes well separated, linear to triangular-ovate, dentate to lobed proximally, main spines slender, 2–7 mm, faces green to gray, thinly to densely arachnoid-tomentose with fine, non-septate trichomes, sometimes villous with septate trichomes along veins, usually ± loose and irregularly deciduous from leaves in age; basal often present at flowering, sessile or winged-petiolate; principal cauline mostly in proximal 1/2, winged-petiolate or sessile, bases narrowed, auriculate, veins often prominently raised on abaxial faces; distal sessile, auriculate-clasping or short-decurrent 1–10 mm, progressively reduced becoming bractlike, often unlobed or less deeply divided and sometimes spinier than proximal. Heads borne singly, terminal on main-stem and branches, sometimes also in distal axils, erect, not subtended by well-developed leaves, collectively forming corymbiform or racemiform arrays. Peduncles (0–) 2–15 cm. Involucres ovoid to hemispheric or campanulate, 2–3 × 1.5–3.5 cm, ± arachnoid-floccose, often glabrate. Phyllaries in 8–10 series, subequal to strongly imbricate, green, linear to lanceolate (outer) to linear (inner), entire, abaxial faces with inconspicuous to prominent glutinous ridge; outer and mid bodies loosely spreading to ascending or appressed, apices subappressed to ascending or spreading, flat, spines ascending to spreading, fine, 2–4 mm; apices of inner commonly flexuous or reflexed, narrow, flat, scarious. Corollas creamy white to purplish, 20–31 mm, tubes 8–14 mm, throats 5.5–10 mm, lobes 6–7 mm; style tips 4–6 mm. Cypselae tan to dark-brown, 5–7.5 mm, apical collars not differentiated; pappi 16–25 mm.

Distribution

V19-111-distribution-map.gif

Calif., Idaho, Mont., Nev., Oreg., Wyo.

Discussion

Varieties 2 (2 in the flora).

Past floras have treated Cirsium cymosum and C. canovirens as separate species. In my examination of these plants across their combined ranges I realized that they are connected by numerous intermediates and that I could find no characters that consistently distinguish them.

Selected References

None.

Key

1 Larger heads 20–35 mm diam.; outer phyllaries elongate, often nearly as long as inner; glutinous ridge narrow, weakly developed Cirsium cymosum var. cymosum
1 Larger heads 15–25 mm diam.; outer phyllaries usually much shorter than inner phyllaries; glutinous ridge prominent, well developed, appearing dark brown on dry specimens Cirsium cymosum var. canovirens

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

... more about "Cirsium cymosum"
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
subappressed +  and ascending or spreading +
innermost +
scarious +
not differentiated +
racemiform +  and corymbiform +
indeterminate +  and determinate +
David J. Keil +
(Greene) J. T. Howell +
winged-petiolate +  and sessile +
auriculate +  and narrowed +
Carduus cymosus +
compound +  and simple +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
pinnatifid;linear-oblong;oblanceolate or elliptic +
2 cm20 mm <br />0.02 m <br /> (?) +
3cm;7cm +
10-nerved or 20-nerved +  and rugose +
ascending;arising +
tawny +  and white +
? (?) +  and ? (?) +
actinomorphic +
creamy white +  and purplish +
2 cm20 mm <br />0.02 m <br /> (3.1 cm31 mm <br />0.031 m <br />) +
tan +  and dark-brown +
compressed +  and ovoid +
fertile +  and bisexual +
less deeply divided and sometimes spinier +, short-decurrent +, auriculate-clasping +  and sessile +
divided +, unlobed +  and bractlike +
0.1 cm1 mm <br />0.001 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Calif. +, Idaho +, Mont. +, Nev. +, Oreg. +  and Wyo. +
green;gray +
deciduous +
villous +  and arachnoid-tomentose +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
indeterminate +
each +  and sessile +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
glabrate +  and arachnoid-floccose +
ovoid;hemispheric or campanulate +
1.5 cm15 mm <br />0.015 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
sessile +  and petiolate +
well-developed +
cauline +  and basal +
bristle-tipped +
linear +  and triangular-ovate dentate +
0.2 cm2 mm <br />0.002 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
2-carpellate +
persistent +
1.6 cm16 mm <br />0.016 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 cm20 mm <br />0.02 m <br /> (15 cm150 mm <br />0.15 m <br />) +
middle +  and outer +
papillate +  and smooth +
sessile +  and winged-petiolate +
Amer. Midl. Naturalist +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
inconspicuous;prominent +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
ascending +  and spreading +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
spiny-winged +, simple +  and branched +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
Cirsium botrys +  and Cirsium triacanthum +
Cirsium cymosum +
species +
cylindric +
expanded +
0.55 cm5.5 mm <br />0.0055 m <br /> (1 cm10 mm <br />0.01 m <br />) +
bristly-dentate to coarsely +
septate +  and non-septate +
arachnoid +  and fine +
perennial +, deciduous +  and biennial +
25 cm250 mm <br />0.25 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
slender +
0.8 cm8 mm <br />0.008 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
perennial +, biennial +  and annual +
5 cm50 mm <br />0.05 m <br /> (400 cm4,000 mm <br />4 m <br />) +
tree +, vine +, shrub +  and subshrub +