Sweet-marsh Butterweed, Tall Butterweed
Senecio hydrophiloides
Synonyms: Senecio
foetidus var. foetidus , Senecio
foetidus var. foetidus, Senecio foetidus var. hydrophiloides, Senecio oreganus
The photo above shows a close-up tightly packed
flower heads that make up the flat-topped inflorescence of sweet-marsh butterweed
as seen at Conboy NWR.........June 18, 2006.
The photo above shows a close-up of the closely-spaced flower
heads of sweet-marsh butterweed as seen at Conboy NWR.........June 18,
2006. Note that the flowers are all discoid.
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The photo at left shows a close-up of one flowerhead
of sweet-marsh butterweed as seen at Conboy NWR.........June 18, 2006.
Note the dark tip to the bracts. The photo at right shows a sideview of the inflorescence of sweet-marsh butterweed, Willard Springs Trail, Conboy Lake NWR.....June 11, 2020.
The photo above shows a close-up of the toothed margin of a stem
leaf of sweet-marsh butterweed as seen along Kreps Lane in Conboy NWR on the
southeastern slopes of Mt. Adams..........June 18, 2006.
Paul Slichter