[Buttercups: The Genus Ranunculus East of the Cascade Mts. of Oregon and Washington]

Large-flowered Swamp Buttercup, Swamp Buttercup

Ranunculus orthorhynchus var. platyphyllus

Synonym: Ranunculus orthorhynchus ssp. platyphyllus

Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

This photo shows a close-up of the flower of western swamp buttercup (var. platyphyllus) as seen in moist meadows along Road #4670 at Billy Meadows Guard Station........June 26, 2008.

Characteristics:

Western swamp buttercup is an attractive perennial wildflower of wet places with several spreading to erect stems from 20-60 cm high. The stems are hollow and are usually branched. The herbage is highly variable, ranging from sparsely to heavily haired. The leaves are mostly basal with a few reduce leaves on the stems. The basal leaves have long petioles to 25 cm long and blades from 3-8 cm long. The blades are pinnately compound with 3-7 leaflets. Individual leaflets are irregularly toothed and lobed into linear, ovate, acute or obtuse segments.

The 5 petals are yellow (occasionally reddish or purplish as noted below) and obovate or oblong in shape, measuring 9-18 mm long. The 5 sepals measure from 6-9 mm and are greenish or often tinged with purple. They are usually reflexed, covered with long straight hairs, and soon deciduous. The stamens number from 50-70.


Varieties:

Variety orthorhynchus: The yellow petals are tinged with red or purple and over twice as long as wide.

Variety platyphyllus: The petals are entirely yellow and are rarely as much as twice as long as wide.


Western Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

This photo shows western swamp buttercup (var. platyphyllus) as seen in moist meadows along Road #4670 at Billy Meadows Guard Station.......June 26, 2008.


Flower of Ranunculus orthorhynchus var. platyphyllus - Flower of Ranunculus orthorhynchus var. platyphyllus

These 2 photos show close-ups of the flowers of western swamp buttercup (var. platyphyllus) as seen in moist meadows along Road #4670 at Billy Meadows Guard Station.......June 26, 2008.

Habitat:

Western swamp buttercup is found in wet meadows, ditches, and slow streams on both sides of the Cascade Mt range.


Range:

Western swamp buttercup may be found from Alaska south to California and east to Montana, Wyoming and Utah.


Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus) - Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus - Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Additional photos of large-flowered swamp buttercup as seen in wetlands along forest service road 14-491, Malheur National Forest........July 3, 2010.

Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus) - Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus) - Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Flower of Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus) - Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

The 5 photos seen above show various close-up views of western swamp buttercup (var. platyphyllus) as seen in meadows near Penland Lake in the Umatilla N. F. northeast of Heppner, OR.........June 22, 2007.

Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Western swamp buttercup in bloom at moist creek crossings of the Lick Creek Trail #1809, Hells Canyon National Recreation Area......July 17, 2019.

Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Western swamp buttercup (var. platyphyllus) as seen in vernally moist grasslands at Summit Prairie, Malheur National Forest.......June 26, 2011.

Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus) - Large-flowered Swamp Buttercup, Swamp Buttercup: Ranunculus orthorhynchus var. platyphyllus (Synonym: Ranunculus orthorhynchus ssp. platyphyllus)

Western swamp buttercup (var. platyphyllus) as seen in vernally moist grasslands at Summit Prairie, Malheur National Forest.......June 26, 2011.

Paul Slichter