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

Texas or Texas purple or southern thistle, Texas thistle

Habit Perennials, subacaulescent and forming compact, rounded mounds, 5–20 cm, or ± erect and to 70(–90) cm; runner roots producing adventitious buds. Annuals or biennials, 20–200 cm; taprooted.
Stems

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

branches 0 or few, ascending.

usually single, erect, tomentose to ± glabrate;

branches 0–many, usually restricted to distal part, ascending.

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 oblong to elliptic, 7–30 × 2–12 cm, unlobed and merely spinulose to irregularly dentate or shallowly to deeply pinnatifid, lobes ± triangular, separated by narrow to wide sinuses, sometimes coarsely dentate or lobed proximally, obtuse to acute, main spines slender to stout, 1–5 mm, abaxial faces arachnoid tomentose, adaxial glabrous or thinly arachnoid;

basal often absent at flowering, petioles slender, ± winged;

cauline progressively reduced, proximal petiolate, mid and distal broadly sessile, bases ± auriculate-clasping or decurrent 1–3 cm;

distalmost linear to lanceolate, bractlike, irregularly dentate or shallowly lobed.

Peduncles

0–10 cm, leafy-bracted.

slender, 3–30 cm (not overtopped by crowded distal leaves).

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 hemispheric, 1.5–2 × 1.5–2 cm, thinly arachnoid, 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.

white to pink-purple, 20–25 mm, tubes 7–10 mm, throats 6–8 mm (noticeably wider than tubes), lobes 4–7 mm;

style tips 3–4 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 8–10 series, imbricate, green, lanceolate (outer) to linear (inner), abaxial faces with prominent glutinous ridge;

outer and middle appressed, bodies entire, acute, spines spreading, slender, 1–5 mm;

apices of inner often flexuous, flat, scabrid-ciliolate, acuminate.

Heads

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

1–many, in openly paniculiform arrays.

Cypselae

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

pappi 20–40 mm.

brown, 3–5 mm, apical collars not differentiated;

pappi 15–16 mm.

2n

= 32.

= 22, 23, 24.

Cirsium quercetorum

Cirsium texanum

Phenology Flowering spring–summer (Apr–Aug). Flowering spring–summer (Apr–Jul).
Habitat Usually dry sites, coastal bluffs, grasslands, oak woodlands, coastal scrub Roadsides, pastures, fields, shrub-tree savannas
Elevation 0–400 m (0–1300 ft) 0–1000 m (0–3300 ft)
Distribution
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; LA; MO; NM; OK; TX; Mexico (Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas)
[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 texanum ranges from the Chihuahuan Desert regions of trans-Pecos Texas and adjacent southeastern New Mexico across the plains of Texas and southern Oklahoma to southwestern Arkansas and southwestern Louisiana and south into north-central Mexico. D. S. Correll and M. C. Johnston (1970) suggested hybridization between Cirsium texanum and C. undulatum to explain anomalous specimens in the Edwards Plateau and trans-Pecos regions of western Texas.

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

Source FNA vol. 19, p. 160. FNA vol. 19, p. 119.
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. pitcheri, C. praeteriens, C. pulcherrimum, C. pumilum, C. quercetorum, C. remotifolium, C. repandum, C. rhothophilum, C. rydbergii, C. scariosum, 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 C. austrinum, C. helleri, C. texanum var. stenolepis
Name authority (A. Gray) Jepson: Fl. W. Calif., 507. (1901) Buckley: Proc. Acad. Nat. Sci. Philadelphia 13: 460. (1862)
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