Cirsium scariosum var. americanum
(Dinnerplate Thistle)
Cirsium scariosum var. americanum, Gould Trail, State Forest State Park, Jackson Co. 0623
Cirsium scariosum var. americanum, Gould Trail, State Forest State Park, Jackson Co. 0633
Cirsium scariosum var. americanum, Gould Trail, State Forest State Park, Jackson Co. 0632
Cirsium scariosum var. americanum, Gould Trail, State Forest State Park, Jackson Co. 0630
Cirsium scariosum var. americanum, Gould Trail, State Forest State Park, Jackson Co. 0616
| Scientific Name | Cirsium scariosum var. americanum (Cirsium americanum) | USDA PLANTS Symbol | CIAM4 |
| Common Name | Dinnerplate Thistle | ITIS Taxonomic Serial No. | 780885 |
| Family | Asteraceae (Sunflower) | SEINet Reference |
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| Description |
Life zones and habitat: Foothills to alpine (7000 to 12500 ft.); meadows, sagebrush scrub, and open areas in woodlands. Plant: Stemless, low-growing biennial/perennial in a large rosette up to 32 inches across. Leaves: Basal rosette; oblong to oblanceolate or elliptic, 4 to 16 inches long with broad central mid-stripe, pinnately lobed or pinnatifid, with spines at lobe tips usually 3/8-inch long or less; upper surfaces smooth or sparsely hairy, lower surfaces with fine, woolly hairs. Inflorescence: Many flower heads clustered together at ground level closely subtended by the basal rosette, each about 1 inch across or less; central disk florets are white to pink-tinged and the protruding styles are creamy-white; no ray flowers; involucre with overlapping phyllaries with spines that are up to 1/2-inch long but usually less. Bloom Period: July to September. References: "Flora of Colorado" Second Edition by Jennifer Ackerfield, Jepson eFlora and Flora of North America. |
BONAP Distribution Map Map Color Key |
Colorado Status: Native |
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Banner photo: Castilleja rhexifolia and a brewing storm over the San Juan Mountains
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