Gray Alder, Mountain Alder, Thinleaf Alder, Thin-leaf Alder
Alnus incana ssp. tenuifolia
Synonyms: Alnus incana var. occidentalis, Alnus incana var. virescens, Alnus x purpusii, Alnus tenuifolia
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Close-up views of the upper leaf surface (left) and lower leaf surface (right) of mountain alder as seen from seeps along the Canyon Mountain Trail #218, Strawberry Mountain Wilderness.........August 19, 2011.
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Close-up views of the upper leaf surface and a leaf bud of mountain alder as seen from the shoreline of the Deschutes River in the eastern Columbia River Gorge..........September 29, 2007.
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Close-up views of the lower leaf surface of mountain alder as seen from the shoreline of the Deschutes River in the eastern Columbia River Gorge..........September 29, 2007.
Mountain alder leaves as seen at the crossing of Whychus Creek along the Alder Springs Trail #855, Crooked River National Grasslands.......May 11, 2018.
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Mountain alder growing in a sedge meadow along Summit Creek where it crosses Forest Service Road 1647, Malheur National Forest.........August 4, 2011.
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Mountain alder growing along the Line Butte Trail #807 on the southern slopes of Lookout Mountain, Ochoco National Forest..........June 22, 2017.
Ventral leaf surface of mountain alder as seen at
Potter Meadows across Forest Road 38 from the southern trailhead for the Ochoco Mountain Trail, Ochoco National Forest.........July 13, 2017.
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Additional photos of mountain alder growing along Forest Service Road #16 at Big Creek in Logan Valley, Malheur National Forest.........August 20, 2011.
Mountain alder observed along Indian Creek at the northwest corner of Big Summit Prairie, Ochoco National Forest.......May 27, 2018.
Paul Slichter