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pasture thistle

cliff thistle

Habit Biennials or monocarpic perennials, 25–100 cm; sometimes perennating by root sprouts. Perennials 15–45 cm; stout, branched caudices.
Stems

erect, villous with septate trichomes and sometimes thinly arachnoid tomentose;

branches 0–few, distal, ascending.

5–30+, horizontal or hanging from cliff sides, thinly appressed gray-tomentose and villous with septate trichomes;

branches 0–few, distal, ascending.

Leaves

blades oblong-elliptic, 5–30+ × 2–10 cm, ± undulate, shallowly to deeply pinnatifid, lobes ovate to broadly triangular, usually separated by broad sinuses, spinose-dentate or lobed, main spines 1.5–7 mm, slender to stout, abaxial faces villous with septate trichomes, at least along veins, sometimes thinly arachnoid, adaxial faces villous with septate trichomes and thinly arachnoid tomentose or subglabrous;

basal often present at flowering, bases tapered;

principal cauline sessile, moderately reduced distally, bases often auriculate-clasping;

distal reduced, similar to proximal.

blades oblong-elliptic to oblanceolate, 5–30 × 1–5 cm, shallowly to deeply pinnatifid, lobes spreading, triangular, coarsely dentate or lobed, obtuse to acute, main spines slender, 4–10 mm, abaxial faces green or gray-tomentose, villous with septate trichomes along midveins, ± glabrate, adaxial green and glabrous or thinly tomentose, ± glabrate;

basal often present at flowering, spiny winged-petiolate;

principal cauline sessile, gradually reduced distally;

distal oblong, bases ± clasping, usually less deeply lobed and often spinier than proximal.

Peduncles

0–15+ cm (above distal leaves), leafy-bracted.

0–1 cm.

Involucres

broadly cylindric to ovoid, 3.5–5 cm, 2.5–3 cm diam. (appearing much wider and hemispheric to campanulate in pressed specimens), loosely arachnoid on phyllary margins or glabrate.

cylindric to narrowly campanulate, 3.5–4.5 × 1.5–2 cm, loosely arachnoid, glabrate, finely short-ciliate.

Corollas

pink to purple (white), 40–60 mm, tubes 20–35 mm, throats 11–15 mm, lobes 7–10 mm;

style tips 3–7 mm.

red to reddish purple, 26–27 mm, tubes 3.5–5 mm, throats 7.5–9.5 mm, lobes 12–14 mm;

style tips ca. 3 mm.

Phyllaries

in 8–10 series, imbricate, ovate or lanceolate (outer) to lance-linear (inner), abaxial faces with ± prominent glutinous ridge, outer and middle appressed, apices ascending to spreading, spines 1.5–6 mm;

apices of middle and inner narrowed and scabrid-denticulate, innermost spineless, tapered and entire or with expanded, erose-denticulate, flexuous tips.

in 5–6 series, imbricate, linear-lanceolate (outer) to linear (inner), entire, abaxial faces without glutinous ridge, apices red to reddish purple, stiffly ascending, long-acuminate, spines straight, 1–10 mm, ± flattened;

apices of inner stramineous to red, straight or flexuous.

Heads

1–few, borne singly at tips of main stem and branches, often closely subtended by 1–several bracts.

1–6+, borne singly or in condensed corymbiform arrays.

Cypselae

stramineous to brown, 3.5–5 mm, apical collars yellow or colored like body;

pappi 35–45 mm.

stramineous, 5–6 mm, apical collars not differentiated;

pappi 20–25 mm.

2n

= 30.

Cirsium pumilum

Cirsium turneri

Phenology Flowering summer (Jun–Sep).
Habitat Crevices in limestone or basaltic cliffs
Elevation 900–1500 m (3000–4900 ft)
Distribution
from FNA
CT; DE; IA; IL; IN; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; PA; RI; SC; VA; VT; WI; WV; ON; United States
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico (Chihuahua, Coahuila)
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Flowers of Cirsium pumilum are reportedly sweetly scented.

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

Cirsium turneri is known from the mountains of the Big Bend area of trans-Pecos Texas and adjacent areas of northern Mexico.

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

Key
1. Spines of outer phyllaries stout, 3–6 mm; plants usually with several long branches; leaves usually lobed nearly to the midvein; roots rarely and only slightly tuberous-thickened; cypselae usually 3.5– 4 mm
var. pumilum
1. Spines of outer phyllaries slender, 1.5–3 mm; plants simple or distally with a few short branches; leaves usually shallowly lobed; roots often tuberous-thickened; cypselae usually 4.5–5 mm
var. hillii
Source FNA vol. 19, p. 116. FNA vol. 19, p. 144.
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. flodmanii, 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. 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. 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. undulatum, C. vinaceum, C. virginianum, C. vulgare, C. wheeleri, C. wrightii
Subordinate taxa
C. pumilum var. hillii, C. pumilum var. pumilum
Synonyms Carduus pumilus
Name authority (Nuttall) Sprengel: Syst. Veg. 3: 375. (1826) Warnock: SouthW. Naturalist 5: 101. (1960)
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