The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Alameda County thistle, brownie or Alameda County thistle, brownie thistle

dune thistle, Pitcher's thistle, sand-dune thistle

Habit Perennials, subacaulescent and forming compact, rounded mounds, 5–20 cm, or ± erect and to 70(–90) cm; runner roots producing adventitious buds. Biennials or short-lived monocarpic perennials, 20–100 cm; taproots long.
Stems

1–10+, erect or ascending, glabrous to thinly gray-tomentose, sometimes villous with septate trichomes;

branches 0 or few, ascending.

1 or few, erect, densely gray-tomentose;

branches 0 to several, ascending to spreading.

Leaves

blades elliptic to obovate, 5–20 × 3–7 cm, strongly undulate, shallowly to deeply pinnatifid with 3–8 pairs of lobes, lobes linear-lanceolate to broadly triangular, (often longer than 2 cm), closely spaced, spreading, spinose-dentate or lobed, main spines slender to stout, 2–15 mm, abaxial faces thinly to densely tomentose, ± villous with septate trichomes along veins, glabrescent or trichomes persistent, adaxial thinly arachnoid-tomentose and soon glabrescent;

basal usually present at flowering, petiolate;

principal cauline petiolate, progressively reduced distally, bases sometimes decurrent as spiny wings to 1 cm;

distal reduced, similar to proximal.

blades elliptic to obovate, 10–30 × 8–14 cm, deeply divided nearly to midveins, lobes ascending to spreading, linear, remote, margins revolute, entire or minutely spinulose, main spines 1–2 mm, faces gray-tomentose, more densely so abaxially;

basal present or withered at flowering, petiolate;

principal cauline well distributed, bases decurrent as linear-lobed to spiny wings 1–3 cm;

distal cauline well developed.

Peduncles

0–10 cm, leafy-bracted.

0–5 cm.

Involucres

ovoid to hemispheric or broadly campanulate, 2.5–5 (in first-formed heads, often smaller in later heads) × 2.5–6 cm, loosely arachnoid on phyllary margins or glabrate.

ovoid to campanulate, 2–3 × 2–3 cm, loosely arachnoid on phyllary margins or glabrate.

Corollas

white or pale lavender to purple, 25–35 mm, tubes 10–20 mm, throats 7–10 mm, lobes 5–8 mm;

style tips 2.5–4.5 mm.

dull white or pinkish-tinged (rarely rich purple), 20–30 mm, tubes 8.5–15 mm, throats 4.5–10 mm, lobes 3–8 mm;

style tips 3.5–5.5 mm.

Phyllaries

in 5–10 series, imbricate, ovate or lanceolate (outer) to linear-lanceolate (inner), margins of outer entire, abaxial faces without glutinous ridge;

outer and mid appressed, spines erect or ascending, (0–)1–2(–10) mm;

apices of mid and inner narrowed and scabrido-denticulate or with expanded, spinuloso-serrate or -dentate tips, spineless or spine-tipped.

in 6–8 series, imbricate, ovate-lanceolate (outer) to linear-lanceolate (inner), abaxial faces with narrow glutinous ridge;

outer and middle appressed, acute, spines ascending to spreading, slender, 1–2(–3) mm;

apices of inner often flexuous, flattened, spineless, scabrid.

Heads

1–few, erect, ± crowded, often closely subtended by distalmost leaves.

1–20+ in corymbiform arrays.

Cypselae

brown, 5–6.5 mm, apical collars colored like body;

pappi 20–40 mm.

light brown, sometimes with darker streaks, 6–7.5 mm, apical collars lighter colored, very narrow;

pappi 15–30 mm, usually noticeably shorter than corolla.

2n

= 32.

= 34.

Cirsium quercetorum

Cirsium pitcheri

Phenology Flowering spring–summer (Apr–Aug). Flowering spring–summer (May–Sep).
Habitat Usually dry sites, coastal bluffs, grasslands, oak woodlands, coastal scrub Sand dunes and beaches
Elevation 0–400 m (0–1300 ft) 180–200 m (600–700 ft)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
IL; IN; MI; WI; ON
[WildflowerSearch map]
[BONAP county map]
Discussion

Cirsium quercetorum occurs in the north and south Coast ranges of California from Mendocino to San Luis Obispo counties. It overlaps in range and habitat with several other thistle species and has been reported to hybridize with C. andrewsii, C. douglasii, C. occidentale, C. remotifolium var. odontolepis, and C. fontinale var. fontinale (F. Petrak 1917; J. T. Howell 1960b). Considerable variation occurs within the range of C. quercetorum, and two of the variants have been given taxonomic recognition as vars. walkerianum and xerolepis. Additional study over the range of the species is needed to determine whether these or other variants should be recognized formally.

Cirsium quercetorum appears to be related to the polymorphic C. scariosum complex. The perennial habit with runner roots of C. quercetorum consistently distinguishes it from the monocarpic C. scariosum.

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

Cirsium pitcheri is endemic to beach and dune habitats around lakes Huron, Michigan, and Superior. It has been extirpated from portions of its former range at the southern end of Lake Michigan. It is threatened by foot traffic, off-road vehicular activity, and clearing and development of beachside habitats. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.

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

Source FNA vol. 19, p. 160. FNA vol. 19, p. 122.
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. pumilum, 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. 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
Synonyms Cnicus quercetorum, C. quercetorum var. walkerianum, C. quercetorum var. xerolepis, C. walkerianum Cnicus pitcheri
Name authority (A. Gray) Jepson: Fl. W. Calif., 507. (1901) (Torrey ex Eaton) Torrey & A. Gray: Fl. N. Amer. 2: 456. (1843)
Web links