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Tracy's thistle

Parry thistle, Parry's thistle

Habit Perennials, 50–200+ cm; tap-rooted. Biennials, 50–200+ cm; taprooted.
Stems

1–several, erect or ascending, thinly gray-tomentose or ± glabrate;

branches few to many, ascending.

1, erect, puberulent to pilose with jointed trichomes, sometimes also thinly arachnoid;

branches 0–many, ascending, often nodding at tips.

Leaves

blades elliptic to oblong, 8–40 × 1–12 cm, margins weakly to strongly undulate, spinose-dentate or shallowly to deeply lobed, lobes ascending to spreading, ± triangular, mostly well separated, spinulose and coarsely dentate or cleft into 2–3 lanceolate to triangular, often entire-margined, spine-tipped divisions, main spines 2.5–7+ mm, abaxial faces densely gray-tomentose, adaxial thinly tomentose;

basal sometimes present at flowering, winged-petiolate;

principal cauline becoming sessile and progressively reduced distally, widest at bases, bases ± auriculate-clasping to short-decurrent;

distal cauline reduced, often spinier.

blades oblong to lanceolate or oblanceolate, 10–30 × 2–5 cm, margins flat to undulate, spinulose and otherwise entire to coarsely dentate or shallowly to deeply pinnatifid, lobes well separated, spinulose to coarsely few-dentate, main spines slender to stout, 1–15 mm, one or both faces thinly pilose, sometimes thinly arachnoid, green and ± glabrescent at maturity;

basal usually absent at flowering, sessile or winged-petiolate;

principal cauline well distributed, proximal absent at flowering, moderately reduced distally, winged-petiolate or sessile (proximal), sessile and auriculate-clasping to slightly decurrent 0–2 cm;

distal well developed, spreading, lobed or unlobed.

Peduncles

0–10+ cm.

0–4 cm.

Involucres

ovoid to hemispheric or broadly campanulate, 2–3 × 1.7–3.5 cm, loosely arachnoid on phyllary margins or glabrate.

hemispheric to subspheric, 1.5–2.5 × 1.5–3 cm, glabrous to finely arachnoid and/or pilose, often long pilose-ciliate with arachnoid trichomes connecting adjacent phyllaries.

Corollas

white to lavender or pink-purple, 23–30 mm, tubes 9–14 mm, throats 5.5–10.5 mm, lobes 5.5–9.5 mm;

style tips 4–7 mm.

ochroleucous to ± yellow (rarely white or purple), 11–17 mm, tubes 5.5–11 mm, throats 2–4 mm, lobes 3–5 mm;

style tips 2–4 mm.

Phyllaries

in 6–10 series, imbricate, ovate to lanceolate (outer) to linear-lanceolate (inner), margins entire, abaxial faces with prominent glutinous ridge;

outer and middle appressed, spines spreading, slender to stout, 2–6 mm;

apices of inner often flexuous, narrow, flat, ± entire, spineless or tipped with weak spines.

in 5–8 series, imbricate to subequal, proximally greenish, distally darker, becoming brownish, linear to narrowly lanceolate, outer often nearly as long as inner, abaxial faces with poorly developed glutinous ridge;

outer and mid bases appressed, apices loosely ascending to spreading, bodies entire to spiny-ciliate or terminal appendages expanded, ± scarious, pectinately fringed, spines straight, 2–6 mm;

apices of inner flat or spine-tipped, sometimes expanded and fimbriate.

Heads

1–many, terminal on branches and often in leaf axils, in leafy, ± corymbiform arrays.

1–many, ± erect, loosely to densely clustered at tip of main stem and branches in subcapitate to racemiform arrays, often also in distal leaf axils, closely subtended by clusters of unlobed to deeply dissected, often very spiny bracts.

Cypselae

light to dark brown, 6–7 mm, apical collars colored like body or rarely yellowish, narrow;

pappi 20–23 mm, usually noticeably shorter than corolla.

tan to dark brown, 4–6 mm, apical collars narrow, not differently colored;

pappi 9–15 mm.

2n

= 24.

= 34.

Cirsium tracyi

Cirsium parryi

Phenology Flowering late spring–summer (Jun–Aug). Flowering summer–fall (Jul–Oct).
Habitat Dry slopes, sagebrush deserts, pinyon-juniper woodlands, openings in montane coniferous forests, often in disturbed areas Stream banks, montane meadows, damp soil in montane coniferous forests
Elevation 1400–2900 m (4600–9500 ft) 2100–3700 m (6900–12100 ft)
Distribution
from FNA
CO; NM; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NM
[WildflowerSearch map]
[BONAP county map]
Discussion

Cirsium tracyi occurs from eastern Utah and western Colorado south in the Colorado Plateau and southern Rocky Mountains to northwestern New Mexico. Large-headed plants of Cirsium tracyi and small-headed individuals of C. undulatum are sometimes difficult to distinguish. P. L. Barlow-Irick (unpubl.) found that although there is much overlap in floral measurements of C. tracyi and C. undulatum, the means for some of these characters are statistically significant. Corolla lobes of C. tracyi, for instance, average about 7 mm and those of C. undulatum about 10 mm. The species differ in chromosome number as well.

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

Cirsium parryi ranges from the Rocky Mountains of central and southern Colorado south to the San Francisco Peaks, Pinaleno Mountains, and White Mountains of Arizona, and the Mogollon and Sacramento ranges of southern New Mexico. Within this broad range several minor variants have been recognized at the species level. The features that supposedly distinguish C. gilense, C. inornatum, and C. pallidum vary widely and inconsistently through the range of the species. In like manner the characters used by Schaack and Goodwin to distinguish subsp. mogollonicum fall well within the variation of the species as a whole and do not seem adequate to separate subsp. mogollonicum from the rest of C. parryi at any taxonomic rank. Cirsium parryi hybridizes with C. grahamii in Arizona and C. canescens in Colorado.

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

Source FNA vol. 19, p. 121. FNA vol. 19, p. 149.
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. quercetorum, C. remotifolium, C. repandum, C. rhothophilum, C. rydbergii, C. scariosum, C. texanum, 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. 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
Synonyms Carduus tracyi, C. acuatum, C. floccosum, C. undulatus var. tracyi Cnicus parryi, C. gilense, C. inornatum, C. pallidum, C. parryi subsp. mogollonicum
Name authority (Rydberg) Petrak: Beih. Bot. Centralbl. 35(2): 424. (1917) (A. Gray) Petrak: Bot. Tidsskr. 31: 68. (1911)
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