Palouse Thistle
Cirsium brevifolium
Synonym: Cirsium palousense
What may be an example of Palouse thistle as seen along the Canyon Mountain Trail #218, Strawberry Mountain Wilderness...........August 19, 2011.
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What may be an example of Palouse thistle as seen along the Canyon Mountain Trail #218, Strawberry Mountain Wilderness...........August 19, 2011.
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Several samples of Palouse thistle as seen along Forest Service Road 5401 several miles downhill to the north of the Malheur National Forest boundary on Baldy Mountain..........June 22, 2011. The leaves of this species can range from unlobed with spinulose or dentate margins to deeply pinnatifid with densely gray lower surfaces and shiny green to thinly tomentose upper surfaces. Note also the strongly imbricate involucral bracts with their spines abruptly spreading outwards.
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Palouse thistle as observed at left along the South Prong Trail #821, Black Canyon Wilderness......June 16, 2019.
What appears to be the basal leaves of Palouse thistle as observedat right along Forest Road 38-200 to Spanish Peak, Ochoco National Forest......September 23, 2023.
Paul Slichter