Lyall's Rockcress, Lyall's Slender Rockcress
Boechera lyallii
Synonyms: Arabis lyallii, Arabis lyallii var. lyallii, Arabis lyallii var. nubigena
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Lyall's rockcress beginning to bloom on gravelly slopes recently devoid of snow near Warm Lake, Goat Rocks Wilderness........July 23, 2016.
Maturing fruits of Lyall's rockcress as observed along the Pacific Crest Trail #2000 in upper Cispus Basin, Goat Rocks Wilderness.......August 19, 2020.
Lyall's rockcress as seen in the drier, upland portions of Gotchen Meadows, southeastern Mount Adams, Gifford Pinchot National Forest............August 8, 2012.
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Lyall's rockcress as seen in the drier, upland portions of Gotchen Meadows, southeastern Mount Adams, Gifford Pinchot National Forest............August 8, 2012. Note the leafy stems, lavender flowers and erect fruits.
Lyall's slender rockcress as seen on sandy soils at about 6800' in the eastern portion of upper Killen Creek basin, Mt. Adams Wilderness.........August 11, 2016.
Lyall's rockcress as seen at Hell Roaring Overlook
at the southeast side of Mt. Adams.............August 7, 2004.
The photo above shows a close-up of the flowers
of Lyall's rockcress as seen along the Highline Trail #114 at about 6900' on Mt. Adams.........July
23, 2005. Note the glagrous sepals and pedicels and the erect fruits
beginning to emerge from between the petals.
The photo above shows a close-up view of of
an oblanceolate basal leaf of Cascade rockcress as seen along the Highline Trail
#114 at about 6900' on Mt. Adams.........July 23, 2005.
The photo above shows the form of Lyall's rockcress
as seen along the Highline Trail #114 at about 6900' on Mt. Adams........July 23,
2005. Plants begin to flower as the stems emerge from the tuft of basal leaves
and the stems elongate as the fruits begin to develop.
A close-up of Lyall's rockcress with maturing, erect fruits. Not the non-clasping stem leaves and basal leaves with long, tapering petioles. Photographed on sandy soils near High Camp at the base of the terminal moraine of the Adams Glacier, Mount Adams Wilderness.........August 19, 2013.
Lyall's rockcress blooming on sandy slopes near the upper part of East Fork Adams Creek just below the terminal moraine for the Adams Glacier, Mt. Adams Wilderness...........August 20, 2013.
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Lyall's rockcress as seen along the Climber's Trail above Hellroaring Overlook at the southeastern corner of Mount Adams...........August 12, 2013.
Paul Slichter