Cardwell's penstemon as seen along the Bull of the Woods Trail #550, Bull of the Woods Wilderness.........September 14, 2018.
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Cardwell's penstemon as seen in subalpine meadows on Silver Star Mt. in the southwestern Gifford Pinchot N.F........July 9, 2008.
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Several exceptionally dark-flowered forms of Cardwell's penstemon as seen on the south side of the Johnston Ridge Observatory, Mt. St. Helens National Monument........June 18, 2018.
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Cardwell's penstemon as seen at treeline along the Butte Camp Trail, Mount Saint Helens National Monument........July 9, 2013.
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Cardwell's penstemon seen at left atop Sister Rocks at the northwestern edge of the Trapper Creek Wilderness.........June 2, 2013. The photo at right shows Cardwell's penstemon blooming along the Butte Camp Trail #38A at timberline, Mount Saint Helens National Volcanic Monument......July 12, 2021.
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Cardwell's penstemon as seen along the Boundary Trail #1 on Johnstone Ridge east of the observatory, Mount Saint Helens National Volcanic Monument..........July 2, 2014.
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Cardwell's penstemon as seen along the Butte Camp Trail #238A aout one half mile downhill from the junction with the Loowit Trail #216, Mount Saint Helens National Monument.........June 9, 2015.
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Cardwell's penstemon blooming along the Loowit Trail on the Plains of Abraham near Pumice Butte, Mount St. Helens National Monument.........July 13, 2016.
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A late-blooming cardwell's penstemon as seen at left on the Pumice Plain, Mount Saint Helens National Monument........July 26, 2015. The photo at right shows Cardwells' penstemon blooming along the Tarbell Trail on the west side of Silver Star Mountain, Gifford Pinchot National Forest......June 9, 2021.
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Cardwell's penstemon as seen along Ed's Trail on the north side of Silver Star Mountain, Gifford Pinchot National Forest........June 3, 2016.
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A very late blooming Cardwell's penstemon as seen at left along the Loowit Trail #216 near the junction with the Toutle Trail #238 (south side of the South Fork Toutle River), Mount Saint Helens National Volcanic Monument..........October 19, 2014. The photo at right shows Cardwell's penstemon as seen along the Butte Camp Trail #238A aout one half mile downhill from the junction with the Loowit Trail #216, Mount Saint Helens National Monument.........July 23, 2017.
Cardwell's penstemon as seen along the Boundary Trail #1 on Johnstone Ridge east of the observatory, Mount Saint Helens National Volcanic Monument..........July 22, 2022.
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Cardwell's penstemon blooming along the Butte Camp Trail #38A at timberline, Mount Saint Helens National Volcanic Monument.....August 11, 2022.
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The photo at left shows Cardwell's penstemon fading out of bloom atop Scott Mountain, Mount Washington Wilderness.....July 18, 2023.