Single Record
Participant Info
- Species
- Cirsium hesperium [Cirsium eatonii var. hesperium] [Cirsium scopulorum] [Cirsium eatonii var. eriocephalum]
- Family
- Asteraceae
- CommonName
- Eaton’s thistle
- Presence
- YES
- Status
- native
- EarliestDate
- 1911
- LatestDate
- 2020
- Ecosystem
- montane, subalpine, tundra
- Geobotanical
- Garitas, SSanjuans
- Counties
- Alamosa, Conejos, Costilla, Hinsdale, Mineral, Rio Grande, Saguache, San Juan
- Passes
- Music, Spring Creek, Stony
- WildlifePreserves
- Wheeler
- Other Localities
- Comments
- This is a high altitude Cirsium, fond of passes. Only recently has it been given species status, by J. Ackerfield (2022), who splits "Cirsium scopulorum," so labeled, into four species: C. culebraense, C. funkiae, C. hesperium, and C. scopulorum. She shows C. scopulorum not occurring in the Watershed, and C. hesperium as present only on the west side of the Valley, in the mountains of Saguache, Mineral, Rio Grande, and Conejos counties. C. hesperium is characterized by an erect terminal cluster of flower heads, deep purple corollas, and purple style branches. So currently as judged by SEINet voucher labels, the exact range of Ackerfield's Cirsium hesperium in the Watershed is problematic. FNA says that C. eatonii var. hesperium, which may be Ackerfield's C. hesperium, is confined to the subalpine of the San Juan Mountains of Colorado. Note that Allred et al. (2020) show C. eatonii in Rio Arriba and Santa Fe counties of New Mexico, but no farther south. The list in Great Sand Dunes Plant Species (2005) includes "Cirsium scopulorum," with current species indicated unknown.
- Annotation