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chardon de Flodman, Flodman's thistle, prairie thistle

fountain thistle

Habit Perennials 30–140 cm; horizontal runner roots that produce root sprouts.
Stems

1–several, erect, gray- or white-tomentose;

branches 0–few, ascending.

1–several, erect, loosely arachnoid-tomentose, glandular-pilose;

branches several to many, spreading.

Leaves

blades oblong-oblanceolate to narrowly elliptic, 4–40 × 1–10 cm, bases usually not decurrent, finely spiny-toothed and undivided to coarsely toothed or deeply pinnatifid, lobes broadly triangular to linear-lanceolate, often revolute-margined, main spines 1–7 mm, abaxial faces white-tomentose, adaxial faces green, thinly tomentose, ± glabrate;

basal usually absent or withered at flowering, winged petiolate;

principal cauline proximally winged-petiolate, distally sessile, well distributed, gradually reduced, bases usually not decurrent;

distal cauline well developed.

blades oblanceolate to oblong or elliptic, 20–70 × 5–16 cm, strongly undulate, shallowly to deeply pinnatifid, lobes coarsely toothed or with triangular secondary lobes, main spines 3–15 mm, abaxial faces more densely tomentose, adaxial densely glandular with short, multicellular trichomes and ± tomentose with fine, arachnoid, non-septate trichomes;

basal often present at flowering, petiolate;

principal cauline well distributed, becoming sessile, gradually reduced distally, bases auriculate-decurrent with broad, spiny-margined wings 3 cm or less;

distal cauline leaves progressively reduced, ± bractlike.

Peduncles

0–5 cm (elevated above distal leaves).

0–7 cm.

Involucres

ovoid to broadly campanulate, 2–3.5 × 2.5–3.5 cm, thinly arachnoid.

(green to purple), hemispheric or campanulate, 1.5–3 × 2–5 cm, glabrous or puberulent.

Corollas

purple (white), 23–36 mm, tubes 12–15 mm, throats 6–8.5 mm, lobes 5–9 mm;

style tips 4–7 mm.

white to pinkish or lavender, 14.5–22 mm, tubes 5–8 mm, throats 4.5–9 mm, lobes 3–8 mm;

style tips 2.5–4.5 mm.

Phyllaries

in 7–12 series, strongly imbricate, greenish with subapical darker central zone, ovate or lanceolate (outer) to linear (inner), abaxial faces with prominent glutinous ridge;

outer and middle entire, bodies appressed, entire, acute, spines abruptly spreading, slender, 2–4 mm;

apices of inner spreading, flexuous, narrow, flattened, finely serrulate, ± scabrous.

in 6–10 series, imbricate, ovate to lanceolate, abaxial faces without glutinous ridge;

outer and mid bases appressed, short, bodies entire to erose or ciliolate (rarely outer spine-margined), apices spreading to recurved or reflexed, long, dilated, adaxially puberulent, spines 1–6 mm;

apices of inner erect or reflexed, flattened or tipped with short spines.

Heads

erect, borne singly and terminal on main stem and branches, or few in corymbiform arrays from distal axils (not subtended by ring of spiny-margined bracts).

few–many, ± nodding, in paniculiform or corymbiform arrays, bracts leafy or much reduced.

Cypselae

light brown, 3–5 mm, apical collars stramineous, 0.5–1 mm;

pappi (white or tawny) 20–30 mm.

brownish, 3.4–5 mm, apical collars tan;

pappi 12–15 mm.

Monocarpic

perennials, 50–220 cm; woody tap-rooted caudices with numerous coarse, fibrous lateral roots, sometimes forming new rosettes from root sprouts.

2n

= 22, 24.

Cirsium flodmanii

Cirsium fontinale

Phenology Flowering summer (Jun–Sep).
Habitat Tallgrass, mixedgrass, shortgrass prairies, meadows, pastures, often in damp soil
Elevation 100–2400 m (300–7900 ft)
Distribution
from FNA
CO; IA; IL; KS; MI; MN; MT; ND; NE; SD; WI; WY; AB; MB; ON; QC; SK
[WildflowerSearch map]
[BONAP county map]
from USDA
c Calif
[WildflowerSearch map]
[BONAP county map]
Discussion

Cirsium flodmanii ranges from Saskatchewan and Alberta south through the northern Great Plains and intermountain valleys of Montana and Wyoming to northeastern Colorado and east through the prairies to Minnesota and Iowa, and in widely scattered locations eastward to northern Illinois, southern Wisconsin, southern Ontario, and southern Quebec. It is known to hybridize with C. muticum and C. undulatum. Hybrids between C. flodmanii and C. undulatum are highly sterile with numerous meiotic irregularities (S. Dabydeen 1987).

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

Varieties 3 (3 in the flora).

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

Key
1. Cypselae 4.1–5 mm; phyllary spines 1–2 mm
var. fontinale
1. Cypselae 3.4–4.1 mm; phyllary spines 2–6 mm
→ 2
2. Longer spines of cauline leaves 10–18 mm; most phyllaries without marginal spines
var. campylon
2. Longer spines of cauline leaves 4–7 mm; many outer phyllaries with marginal spines
var. obispoense
Source FNA vol. 19, p. 120. FNA vol. 19, p. 161.
Parent taxa Asteraceae > tribe Cardueae > Cirsium Asteraceae > tribe Cardueae > Cirsium
Sibling taxa
C. altissimum, C. andersonii, C. andrewsii, C. arizonicum, C. arvense, C. barnebyi, C. brevifolium, C. brevistylum, C. canescens, C. carolinianum, C. ciliolatum, C. clavatum, C. crassicaule, C. cymosum, C. discolor, C. douglasii, C. drummondii, C. eatonii, C. edule, C. engelmannii, C. foliosum, C. fontinale, C. grahamii, C. helenioides, C. hookerianum, C. horridulum, C. hydrophilum, C. inamoenum, C. joannae, C. kamtschaticum, C. lecontei, C. longistylum, C. mohavense, C. muticum, C. neomexicanum, C. nuttallii, C. occidentale, C. ochrocentrum, C. ownbeyi, C. palustre, C. parryi, C. perplexans, C. pitcheri, C. praeteriens, C. pulcherrimum, C. pumilum, C. quercetorum, C. remotifolium, C. repandum, C. rhothophilum, C. rydbergii, C. scariosum, C. texanum, C. tracyi, C. turneri, C. undulatum, C. vinaceum, C. virginianum, C. vulgare, C. wheeleri, C. wrightii
C. altissimum, C. andersonii, C. andrewsii, C. arizonicum, C. arvense, C. barnebyi, C. brevifolium, C. brevistylum, C. canescens, C. carolinianum, C. ciliolatum, C. clavatum, C. crassicaule, C. cymosum, C. discolor, C. douglasii, C. drummondii, C. eatonii, C. edule, C. engelmannii, C. flodmanii, C. foliosum, C. grahamii, C. helenioides, C. hookerianum, C. horridulum, C. hydrophilum, C. inamoenum, C. joannae, C. kamtschaticum, C. lecontei, C. longistylum, C. mohavense, C. muticum, C. neomexicanum, C. nuttallii, C. occidentale, C. ochrocentrum, C. ownbeyi, C. palustre, C. parryi, C. perplexans, C. pitcheri, C. praeteriens, C. pulcherrimum, C. pumilum, C. quercetorum, C. remotifolium, C. repandum, C. rhothophilum, C. rydbergii, C. scariosum, C. texanum, C. tracyi, C. turneri, C. undulatum, C. vinaceum, C. virginianum, C. vulgare, C. wheeleri, C. wrightii
Subordinate taxa
C. fontinale var. campylon, C. fontinale var. fontinale, C. fontinale var. obispoense
Synonyms Carduus flodmanii, C. oblanceolatum Cnicus fontinalis
Name authority (Rydberg) Arthur: Torreya 12: 34. (1912) (Greene) Jepson: Fl. W. Calif., 505. (1901)
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